We have Windows application (MSI install package), downloadable from our site. The problem is, that browsers and 3rd party antiviruses prevent some users from download an APP. Is there a way to make our MSI package more trustable for browsers and antivirus? Maybe it can be checked and uploaded in some other resource, and downloadable for users from here?
P.S. We use code signing certificate, and Windows store is not a variant for us now.
Reputable anti-virus vendors have a way you can send your installation packages to be "whitelisted". Browsers have their own heuristics and using an EV certificate (more expensive) is supposed to help. Edge also supposedly respects the Defender whitelist.
Ultimately, the more downloads you get, the better your URL's reputation, the better you pass the heuristics.
We've been building and releasing the same application for almost 20 years and AV false positives can still create problems. This is how we do it today:
After each release, we scan our new setup on https://www.virustotal.com/gui/home/upload and if we notice any AV vendors flagging it we reach out to each of them and submit a request for false positive removal. They all have some form or email address where you can contact them.
They usually process these requests in a few days, so no real big problem for our users and doesn't take a lot of time.
Now, with SmartScreen, there is another story. Even if our package was digitally signed for over a decade, 2 years ago when we renewed our certificate Windows flagged our installer for about 2-3 months.
This was an installer with hundreds of thousands if not millions of users in the last decade. In the end, its reputation system got back to normal and stopped flagging it but it was really annoying for our customers.
The solution to this is to buy an EV certificate (confirmed by some of our customers) and then you will get an instant reputation with SmartScreen. This Spring our normal certificate expires and we will go the EV route too.
You can read more about digital signing and EV certs in the following articles:
Why EV Code Signing? EV Code Signing vs. Regular Code Signing
How to avoid the "Windows Defender SmartScreen prevented an unrecognized app from starting" warning
My company distributes an installer to customers via our website. Recently when I download via the website and try to run the installer I get the warning message:
Windows protected your PC
Windows Defender SmartScreen prevented an
unrecognized app from starting. Running this app might put your PC at
risk.
If I right-click on the installer and choose Properties I note the following:
Our installer is signed.
How do I find the reason for the Windows Defender SmartScreen warning?
I have not managed to find any log file for Windows Defender nor found anything in the Event Viewer.
TL;DR
This warning is shown if your app doesn't have enough reputation with Microsoft SmartScreen yet. In order to gain reputation, you can either
submit your app for malware analysis to Microsoft,
buy an "Extended Validation" code signing certificate,
buy a standard code signing certificate, or
just wait for a long time.
Read on for the details about these different options.
Option 1: Submit your app for malware analysis to Microsoft
Microsoft allows software developers to submit a file for malware analysis. According to Microsoft, this will help developers to "validate detection of their products". If the review was successful, the Microsoft SmartScreen warnings will go away faster, or sometimes even instantly (it worked instantly for one of my own apps). You need to have a Microsoft account to submit your app for review.
However, note that if you release an updated version of your app, then you'll also have to request a new review again. To overcome this problem, you'll either have to use an "Extended Validation" or a standard code signing certificate (see below).
Option 2: Buy an "Extended Validation" code signing certificate
A guaranteed way to immediately and permanently get rid of the Microsoft SmartScreen warnings is to buy an "Extended Validation" (EV) code signing certificate from one of the Microsoft-approved certificate authorities (CA's), and to sign your app with that EV certificate.
Such an EV certificate will cost you somewhere between 250 and 700 USD per year, and will only be issued to registered businesses. If you're a single developer, you must be a sole proprietor and have an active business license. You can read more about the formal requirements for EV code signing certificates in the EV Code Signing Certificate Guidelines.
An EV certificate will typically be shipped to you by physical delivery on a hardware token.
Option 3: Buy a standard code signing certificate
You can also buy a cheaper "standard" (i.e. non-EV) code signing certificate, and sign your app with that certificate. This will also permanently, but not instantly, make the Microsoft SmartScreen warnings disappear. Standard code signing certificates will cost you between 100 and 500 USD per year, and can also be issued to private developers without an active business license. Some CA's also offer discounts for open source projects.
No instant solution
The problem with standard code signing certificates is that they do not instantly silence Microsoft SmartScreen. Instead, some time will be needed for your certificate to build reputation before the warning will go away. However, once your certificate has built enough reputation, all applications signed with that certificate will be permanently trusted by Microsoft SmartScreen and won't trigger the warning anymore.
How long will it take?
So, how long will it take until the Microsoft SmartScreen warning will disappear when using a standard code signing certificate? Unfortunately, this is difficult to answer, since Microsoft itself refuses to publish any details about this. According to inofficial numbers reported by various sources (see below), it usually takes between 2 and 8 weeks until the warning will permanently go away. It seems that the exact duration also depends on the reputation of the website from which your app is downloaded.
The inofficial numbers are:
18 days and about 430 app installs. Source: one of my own certificates (Dec 2022)
42 days and about 1.400 app installs. Source: one of my own certificates (Feb 2021)
16 days and about 2.000 app installs. Source: one of my own certificates (May 2020)
One month and more than 10.000 downloads. Source: here (Jan 2020)
Between a few weeks and a month. Source: here (Dec 2019)
About 2-3 weeks. Source: here (Dec 2019)
About 3.000 downloads. Source: here (Dec 2013)
The problem of certificate rollover
Certificate rollover occurs when your old certificate expires and you begin signing your code with a renewed certificate.
It's a good idea to buy your standard code signing certificate with the longest possible validity period because when you renew your certificate, the reputation will unfortunately not automatically carry over to the renewed certificate (not even if it's signed against the same private key as the old certificate).
However, you can mitigate the rollover problem by getting your renewed code signing certificate before your old certificate expires, and then using both the old (but not yet expired!) and the renewed certificate to sign your code, resulting in two signatures. The signature from your old certificate will continue to bypass SmartScreen and, at the same time, the new signature will help the new certificate to build up trust. So, the idea is that your new certificate becomes trusted before your old certificate expires.
If your old certificate should already have expired, then you can (and should!) still add the signature from your renewed certificate to an already released version of your app, in order to gain reputation for the renewed certificate.
To correctly dual-sign your app, first sign your code with the old certificate, and then sign it again with the renewed certificate, using the /as command line option of Microsoft's SignTool to append an additional signature to the first one (instead of replacing it).
Option 4: Just wait for a long time
If you don't take any measures at all, the Microsoft SmartScreen warning will also go away eventually. This might however take a ridiculous amount of time (months) and / or downloads (tens of thousands). Another big problem is that each time you'll release an updated version of your app, the waiting period will start all over again. So, this probably isn't the solution you're looking for.
After clicking on Properties of any installer(.exe) which block your application to install (Windows Defender SmartScreen prevented an unrecognized app ) for that issue i found one solution
Right click on installer(.exe)
Select properties option.
Click on checkbox to check Unblock at the bottom of Properties.
This solution work for Heroku CLI (heroku-x64) installer(.exe)
If you have a standard code signing certificate, some time will be needed for your application to build trust. Microsoft affirms that an Extended Validation (EV) Code Signing Certificate allows us to skip this period of trust-building. According to Microsoft, extended validation certificates will enable the developer to immediately establish a reputation with SmartScreen. Otherwise, the users will see a warning like "Windows Defender SmartScreen prevented an unrecognized app from starting. Running this app might put your PC at risk.", with the two buttons: "Run anyway" and "Don't run".
Another Microsoft resource states the following (quote): "Although not required, programs signed by an EV code signing certificate can immediately establish a reputation with SmartScreen reputation services even if no prior reputation exists for that file or publisher. EV code signing certificates also have a unique identifier which makes it easier to maintain reputation across certificate renewals."
My experience is as follows. Since 2005, we have been using regular (non-EV) code signing certificates to sign .MSI, .EXE and .DLL files with timestamps, and there has never been a problem with SmartScreen until 2018, when there was just one case when it took 3 days for a beta version of our application to build trust since we have released it to beta testers. It was in the middle of the certificate validity period. I don't know what SmartScreen might not like in that specific version of our application, but there have been no SmartScreen complaints since then. Therefore, if your certificate is a non-EV, it is a signed application (such as an .MSI file) that will build trust over time, not a certificate. For example, a certificate can be issued a few months ago and used to sign many files, but for each signed file you publish, it may take a few days for SmartScreen to stop complaining about the file after publishing, as was in our case in 2018.
We didn't submit our software to Microsoft malware analysis. Microsoft started to provide this service in 2017. It may be a viable alternative to an Extended Validation (EV) certificate.
In conclusion, to avoid the warning altogether, i.e., prevent it from happening even suddenly, you need an Extended Validation (EV) code signing certificate, and/or, you can submit your software to Microsoft malware analysis.
UPDATE: Another writeup here:
How to add publisher in Installshield 2018
(might be better).
I am not too well informed about this issue, but please see if this answer to another question tells you anything useful (and let us know so I can evolve a better answer here): How to pass the Windows Defender SmartScreen Protection? That question relates to BitRock - a non-MSI installer technology, but the overall issue seems to be the same.
Extract from one of the links pointed to in my answer above: "...a certificate just isn't enough anymore to gain trust... SmartScreen is reputation based, not unlike the way StackOverflow works... SmartScreen trusts installers that don't cause problems. Windows machines send telemetry back to Redmond about installed programs and how much trouble they cause. If you get enough thumbs-up then SmartScreen stops blocking your installer automatically. This takes time and lots of installs to get sufficient thumbs. There is no way to find out how far along you got."
Honestly this is all news to me at this point, so do get back to us with any information you dig up yourself.
The actual dialog text you have marked above definitely relates to the Zone.Identifier alternate data stream with a value of 3 that is added to any file that is downloaded from the Internet (see linked answer above for more details).
I was not able to mark this question as a duplicate of the previous one, since it doesn't have an accepted answer. Let's leave both question open for now? (one question is for MSI, one is for non-MSI).
I understand the code signing.
But when I try to download some application, it doesn't even have code signing.
And it can still open without the Windows Defender blue screen.
Example: http://www.eainstall.com/download
How do I do that?
The Windows SmartScreen alert will go away after enough people download it.
If your software is not that popular then the warning will never go away and there is not much you can do about it.
SmartScreen checks files that you download from the web against a list of reported malicious software sites and programs known to be unsafe. If it finds a match, SmartScreen will warn you that the download has been blocked for your safety. SmartScreen also checks the files that you download against a list of files that are well known and downloaded by many people who use Internet Explorer. If the file that you're downloading isn't on that list, SmartScreen will warn you.
Microsoft SmartScreen & Extended Validation (EV) Code Signing Certificates:
Code signing is important
to our reputation intelligence because this higher level identity allows us to build
reputation across multiple programs signed by a publisher. It is also important
for publishers because signed programs inherit the reputation of the certificate
with which they are signed; this means every program a publisher distributes doesn’t
need to build reputation individually.
...
Programs signed by an EV code signing certificate can immediately establish reputation
with SmartScreen reputation services even if no prior reputation exists for that
file or publisher.
We offer a Windows program downloadable as an InstallShield EXE from our website.
When someone running IE9 attempts to download and run our software, they see the following message at the bottom of their screen:
PROGRAMNAME.exe is not commonly downloaded and could harm your computer.
[DELETE] [ACTIONS] [VIEW DOWNLOADS]
I've read http://blogs.msdn.com/b/ie/archive/2011/03/22/smartscreen-174-application-reputation-building-reputation.aspx
It suggests:
Digitally sign your programs with an
Authenticode signature.
Ensure downloads are not detected as
malware.
Apply for a Windows Logo.
We've done all three things. Our EXE is digitally signed with an authenticode signature (and the bar above the warning message is orange, not red, indicating that IE9 recognized and verified the signature). Our download is not detected as malware by any antivirus program we've tried. And we have applied for and received a Windows Logo.
As yet, most of our customers are not using IE 9. But this is very troublesome to those who do. Is there anything else we can do about this, or do we just have to wait until a critical mass of customers have downloaded this software before this message will go away?
(Does that mean when we release a new version, all IE 9 users will get this message again until enough of them have downloaded it?)
UPDATE 2011-06-14:
Thanks, #EricLaw-MSFT. URL is http://dakim.dakiminc.netdna-cdn.com/DakimBrainFitness.exe . (It's found on the "Download Free Trial" button on http://www.dakim.com .)
We've only been offering downloadable trials for a short while. Our primary distribution method is installation DVDs.
Extended Validation Code Signing Certificates don't suffer from the need to build reputation slowly according to this post:
Reputation is generated and assigned to digital certificates as well as specific files. Digital
certificates allow data to be aggregated and assigned to a single certificate rather than many
individual programs. Although not required, programs signed by an EV code signing certificate can immediately establish reputation with SmartScreen reputation services even if no prior reputation exists for that file or publisher. EV code signing certificates also have a unique identifier
which makes it easier to maintain reputation across certificate renewals. Only Authenticode
Certificates issued by a CA that is a member of the Windows Root Certificate Program can establish
reputation.
At this time, Symantec and DigiCert are offering EV code signing certificates.
In an effort to improve my answer, I've added a link to a similar question I asked and eventually answered myself.
I have made an application for Windows & everytime I run the application by opening the executable file I get the "Publisher Unverified" warning in Windows. It is fine if I was the only audience for this app but thats not the case. Is there any way to program my app such that this message does not show up for the users.
The only way to do this is to obtain and use a code signing certificate from a trusted source. Microsoft calls this Authenticode.
Unfortunately for the little guy, these cost. Verisign sells theirs for about four hundie a year.
Here are some starting points you should read about Authenticode:
http://msdn.microsoft.com/en-us/library/ms537359(VS.85).aspx
http://technet.microsoft.com/en-us/library/cc750035.aspx
http://msdn.microsoft.com/en-us/library/aa379872(VS.85).aspx
Some certificate dealers:
http://www.verisign.com
http://www.thawte.com
http://www.globalsign.net
http://www.geotrust.com
For a cheaper code signing certificate, you can use Comodo. There is a reseller called KSoftware which sells their certificates for $99/yr:
http://www.ksoftware.net/code_signing.html
I used them a few years ago and had no problems.
You can then use SignTool from the .net SDK to sign your EXE files. There is a tutorial here:
http://www.tech-pro.net/code-signing-for-developers.html
I think there is a way to resolve this. We need to add digital signature to the executables. The way to add digital signatures is very nicely outlined at,
http://blog.didierstevens.com/2008/12/30/howto-make-your-own-cert-with-openssl/
http://blog.didierstevens.com/2008/12/31/howto-add-a-digital-signature-to-executables/
Basically we will use OpenSSL to create our own digital signatures and then use the SignTool application by Microsoft to add it to our executable.