I have a script, which monitors some folder's subfolders, check their created date, and if DateDiff from created time and Now is more than 730(2 years) it deletes this folders. The problem is in that, if set current time on PC for 5/16/2015 - the script will delete folders, and it's not cool. I thought about getting time from some internet service, but there is no guarantee that PC will be connected to internet. So I tried to get BIOS time (I believe no users can change it to wrong), and compare folder's created time with this time. But, unfortunately I didn't find the way how to do that. Maybe you have any idea how to implement this task?
Having an incorrect date and time on a production-level machine is not an option nowadays. It will break a lot of things like HTTPS sites (they will fail to validate because of expired certificates), etc.
The system clock (BIOS time) is changed by the operating system whenever the time itself is changed in the OS, so you only have one clock in the computer. In other words the OS does not have a separate clock to track time with.
Nowadays most computers use the Network Time Protocol to keep their clocks in sync, so you should specify the correctly set time as a pre-requisite for your software. (Or you can just specify that the computer must be connected to an external atomic clock, but that's going to be expensive.)
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In my environment we are using Windows 10 Pro version for analytical applications. Sometimes unexplainedly time and date was going to back date.
We have changed the cmos battery, but after half a week of the analysis the date and time got changed again.
This type of issue may lead to data integrity issues.
Any suggestion on this is appreciated.
It may be, that Windows 10 updates the time and does not know where it is. It may then apply a different time zone.
I would turn off automatic date changes in the settings first and then see if this is the issue.
There is software that synchronizes the time with an atomic clock. This would probably be better if you rely on the time and have an internet connection available.
While running vagrant up --provision, getting following error:
One of the issues that I have occasionally struggled with in Hyper-V is that of time synchronization. Right now, for example, the time on my Windows 10 desktop that I am using to write this article is 9:37 p.m. However, the Hyper-V host that I am watching on another monitor is displaying a time of 9:33 p.m.
On the surface, a few minutes of clock skew might seem like a non-issue. However, there are several reasons why the differing clocks are problematic.
One such reason is that the Kerberos protocol, which is heavily used by the Windows operating system, is time-sensitive. If two systems' clocks are more than a few minutes out of sync with one another, it can cause Kerberos to stop working.
Another reason why clock skew is such a big deal is because multi-tier applications often span multiple Hyper-V hosts. A database server might, for instance, reside on one host, while a Web front end exists on another host, possibly even within a different host cluster.
when looking at start_vm.ps1, it seems to use command Start-VM.
and since this seems to be Windows, the Event Viewer might tell why it crashes.
I'd have a look at event channel Hyper-V-Config or Hyper-V-Worker.
command Test-VHD might also be worth a try.
I am not getting event log and do not understand it.
I have a simulator application which writes some enrypted data into a text file. The information that it writes also has the timestamp (which the application picks from system time) along with it which I can not see. I have automated this whole task of sending random data from application to the text file but I want that the records must be written with some time interval in between.
For this I can either put delay in my automation script or I can change the system time every time a new record is inserted.
If I adopt the second approach i.e. I programatically change the system time very frequently (about once in every second) would it cause any harmful effect on the Windows system on which I am running this application ? Would any other critical system processes get affected by it ? Is this approach advisable ?
The best option here is just going to be putting in a delay in the automation script. I can't think of any problems that would arise from changing the system clock every second, but it's best just to let that be handled by the CMOS and any time syncing instead of setting it to change every second.
Changing the System Time might solve your problem, but at the same time it might have adverse affects on time dependent other applications sharing the same System. For example, the automatic antivirus signature updates are time dependent and might get impacted by explicitly changing the System Time or an automatic System Time adjustment for day light saving might get triggered at an inappropriate time. Keeping this issue in mind, the best bet would be to ensure that your application runs on an isolated environment i.e. ensure that other time dependent applications are not present in the same system and also to ensure that auto updates are kept off.
Changing the system time requires administrative privileges, so users of your application will be unable to run it as ordinary users.
I saw this question in a forum about how an application can be developed that can keep track of the installation date and show trial period expired after 30 days of usage. The only constraint is not to use the external storage of any kind.
Question: How to achieve this?
Thanks
Bala
--Edit
I think its easy to figure out the place to insert a question work. Anyway, I will write the question clearly. "external storage" means don't use any kind of storage like file, registry, network or anything. You only have your program.
Use the file-modified date of the file containing the program as the installation date.
I like Doug Currie's idea of the file-modification date. But if the application is downloaded from the web, every night at midnight it gets relinked with new initialized data containing the new expiration date. Then any binary downloaded that day expires on the date given.
If you like, sign the date with a private key so it can't be hacked. Include a public key in the app and decrypt the date. If not correctly signed, hasta la vista, baby.
I don't know if this is possible, as most work I've done has been with embedded systems in which I don't even need to touch the operating system. But would the following be possible?
When compiling your program, leave some extra space at the end (say, 8 bytes), all set to 0. When your application is run, it fetches those bytes and if they're all 0, replaces them with the current time (That's the part I'm not sure about. Does the OS let you do that? If not, there might be some work-arounds using multiple processes.), otherwise, if the time difference is greater than 30 days, it notifies the user that the trial period has ended.
Of course, that method would be vulnerable to resetting the system clock.
If you can't use any external storage at all (not even config files or anything like that), you would need to code it into the app itself so the app's main method (or some method) checks if the current date is less than some expiration date. Part of your installer could actually compile that code on the fly and then it would be set to the installation date. This could be easily defeated by reinstalling the app, but then again, it's not realistic to have no external storage either.
I think the only way to do this generally would be to have your application spawn something off in a separate process that would continue to run and keep track of the date/time even if the main application were closed. When it was restarted, it would then connect to the running process to see if the trial period had expired.
Of course, this would only work if the computer was never restarted and the user never hunted down your spawned process and killed it, which is pretty unlikely. If your application does not do anthing IO-related (file system, registry, something on the network etc.), then a simple restart will wipe away anything that you've done.
So, to summarize: it's not really possible.
I have node-locked licensing working, using the MAC address and system time. We're concerned that people will just edit their system date to extend a license, so I've tried getting the real date from an machine in the NTP pool. That works, but then obviously you can't use the product without being online, and it doesn't seem to be 100% reliable (I'm guessing the UDP packet never arrives/returns in some cases).
What's the standard approach here? Live with the changeable OS date? Run something on a web server that provides the time over TCP? I hear the BIOS date gets updated by the OS when you reboot, so perhaps there isn't any way to know for sure what the current date is without using the internet?
I know that licensing can never be completely secure, and I expect it to be cracked or torrented, but I don't want it to be as easy as changing the system date. Any ideas appreciated. Thanks
Using a hard disk drive serial number in addition to the date would be more difficult to bypass. You can also have it limited to the user login name. Other than having a hardware dongle, software licensing can always be circumvented.
Update:
If that's the case, can't you just monitor the time? Create an algorithm that validates the system clock follows a logical progression (always increasing.) If the date ever suddenly get shifted back more than a specified amount of time (you have to account for some drift and internet time server corrections), you disable the program until the user restores the clock?