I have a file which can be edited from several different places over an intranet, but needs to be kept up to date on one specific machine.
The way things work is like this.
We have a local intranet where changes to the file are made and viewed on the intranet copy of the live website. If everything looks good, the file may then be uploaded to the remote server, overwriting the previous version.
It isn't ideal, I know, but thats the way it has to be.
What I would like to do is keep track of any changes to that remote version of the file so I can then reflect that change on my local machine.
The idea I've had so far is to use the Task Scheduler on the remote server to send an email to me whenever a change takes place. Changes aren't foreseen to happen often, but when they do, I need to know about it.
My problem is, I'm not sure what events to look for in Task Manager. As it stands, the file could be changed by someone FTPing into the server and changing it or by someone remoting in and uploading that way. As I said, not ideal, but its what I have to work with.
To keep things specific, I'm looking to use Task Scheduler here, working off a trigger. From there, I'm a little lost.
As it turns out, I found a better/more useful/"good enough" solution, by creating a FileSystemWatcher and starting it when the application starts.
Thats where the "good enough" comes in, since it won't catch any changes if the application is stopped for some reason. However, since I'm the only one likely to stop the application, things will be a bit more serious than a broken FileSystemWatcher if it comes to that.
Specifically, I created a class called "Utilities" and created the FileSystemWatcher in there.
Then in the Global.asax.cs Application_Start() method, I initialised the FileSystemWatcher and set it going.
If a change takes place, the event handler of the watcher is set to fire off an email to me, with the new file attached.
Simples.
Related
I have a VB6 application that I provide support for. This application works on both Windows XP and Windows 7. Some users were migrated from Windows XP to Windows 7 using the User State Migration tool. These users now receive a generic "Application has crashed" Windows error message when they open certain screens (forms) in the application. My assumption is that there is a missing dll/ocx reference, but I'm having trouble tracking it down.
I've tried many/varied troubleshooting techniques:
Full uninstall and reinstall of my application
Manually re-registering all dll's and ocx's that I know are used
Running Process Monitor on a broken computer and a working computer to compare what dll's and ocx's are accessed. The answer might be here but even after filtering out most of the background noise the amount of data is overwhelming. At a minimum I reviewed all of the calls right before it crashes and all of the calls that were not successful. All of the non-successful calls match between working and non-working.
Installed the Windows Debugger Tools and captured a crash dump. Analyzed the crash dump with DebugDiag. DebugDiag says the exception is in msvbvm60.dll. I tried building a PDB file for my exe and loading it in DebugDiag to get more detail about where the exception is occuring but DebugDiag doesn't want to accept the PDB (might be doing something wrong here, but it just seems to ignore it. This same PDB file works fine when I do remote debugging, however.)
I recompiled my VB6 program without any optimizations in PCode. I've read online that sometimes building in PCode, while bad for performance, will tell you the real exception.
Used the above created PDB file to remote debug the VB6 application. The debugger says that the application crashes after the new window has been created, on a line that sets MousePointer = vbHourGlass... To me it seems unlikely that this is the real cause of the error. There are at least 20 other locations in the program where this same line is called and all work fine.
(Forgot about this one)
Used Dependency Walker and profiled the application on both a working and non-working computer. All errors found by dependency walker were the same between the two computers. There were no additional dependencies found on a working computer, and all missing dependencies on the non-working computer were also missing on the working one.
None of these actions changed my error message or showed me what the error is (unless it really is the mouse cursor issue)... There are no entries in the Windows Event Log related to the app crash.
The non-working and working computers all have the same base Windows 7 image, the only difference is whatever is being changed by USMT, which further convinces me that this is some kind of quirky configuration change or a missing dll/ocx or perhaps an unregistered dll/ocx.
Any ideas or thoughts on how I can track down the root cause of the issue would be greatly appreciated.
Update 1 - Response to questions
#MarkHall I have tried running it as admin, though not with UAC off. The application runs fine on a Windows 7 box as a non-admin with full UAC. Windows XP was 32-bit, Windows 7 is 64-bit, but again it works just fine on a like for like box where the user was not migrated from Windows XP.
#Beaner It's possible that it stores settings somewhere that have been corrupted, but the remote debugging leads me to think that it's more likely something else since it seems to die on a step related to the UI, which then makes me think it's probably a missing dll/ocx reference.
#Bob77 The application is installed into Program Files (x86). While many of the libraries do reside in the same folder, they are all registered.
Peter, often I've noticed that the debugger will indicate a line of code that is actually incorrect, depending on WHERE in the actual assembly language the fault occurs. You should look REAL close around your statement that sets the cursor to vbHourGlass. Your exception is PROBABLY happening BEFORE that line of code, but that line is what the debugger thinks is the actual faulted line of code.
Since you said it happens when a window OPENS, I'd look real close at any ocx's you may have referenced on the form, but perhaps NOT actually being used, or called. You might have one there that you don't intend to be there, that could be causing security issues, or something on Win7? Edit the .frm file by hand if you have to, and look at all the GUIDs the form references.
It is possible that one machine is using PER-USER registration, and the other is using PER-SYSTEM registration?? I don't know...
I would take a much closer look at the form that you are trying to open, and be VERY cautious of everything you are doing in the form load events, and so on. This sounds like it could be something as stupid as Windows Aero being enabled on one system, and not another, or some other sort of "Theme" setting that is throwing the VB Form Rendering routine into a hissyfit... Perhaps even something as stupid as a transparent color index in the icon you selected for that from?
If you are still developing this app, (or at least maintaining it), create an entirely NEW form, and re-create all the controls, etc, on the form (resist the temptation to copy/paste them from the old one...), and then see if THAT does the trick. Then, copy all the event code to the new form one event at a time, with at LEAST enough event code to make the form function, even if it's just a "dead form", that loads no data, or whatever the form is supposed to do. Check and debug after each change, and you WILL find it eventually. Of course, make sure you isolate one of the defunct systems to have a platform that you can duplicate the issue on, or then it's just guessing. I find that using something like Acronis w/ Universal Restore is a great option to then take the image file into a good HV, like VirtualBox, and then restore that image as a VM, so you can debug without interfering with your actual users. This sounds like a lot of work, but then again, so is re-writing an application that already exists, right? :)
Failing THAT... /* and */ are your friends!! (Well, we're dealing with VB, so ' would be your best friend! heh... But I'd start commenting out all the code on the form until that sucker opens. Then once it opens, start putting one line back at a time, and re-running it... That's called "VooDoo Debugging", but sometimes, you gotta do what you gotta do...
THANKS A LOT PETER! :) Now you got ME so involved in this, I feel like I'M the one debugging this sucker! Like if it was MY code I was trying to fix! :)
Let me know if any of this helps... I am actually quite interested in what you discover.
On certain programs you can run them on a demo period for say 'ten tasks' or '5 hours' before you need to decide to purchase them to keep using them, but if you delete and uninstall the program then reinstall it, it knows that its been previously installed and wont let you run the demo again.
How does it do this ? When you download it does it send a identifiing number (ip ?) to the cdn to let it know youve downloaded it before, or when the program itself installed does it check to see traces of previous installation ?
Most "demo" software does this by a feature borrowed from malware: Incomplete deinstallation. A file or registry key belonging to the software is not removed on deinstallation. On reinstallation the software sees the remainder and can act on it.
Often-used hiding places for such a remainder were the system directory (before UAC arrived), but many register some class GUID - nobody I know of has a real overview of which classes in the registry are or are not genuine.
There are many ways this can be implemented.
The easiest way to implement (and also the easiest way to bypass)
On first run, create a registry (or text file) entry somewhere
Add 1 to the counter every time the task (or the app) is run
Do not include this file/registry in the installer app (so it will persist after uninstallation)
If at any time the count is too high, notify the user that the trial has expired.
Using image diff tools this method is pretty easy to identify and overcome.
The hardest method to overcome or bypass is to use a server. On the first run, generate a hash code based on the users computer name, drive serial number, etc, and post this to your server. The server then tracks this as a unique installation, and allows the app to run. Each time you run the app, you update the server. This way, the user cannot find the breadcrumbs and delete them, since they are on your server. The down side, is that this method will require an Internet connection.
There are probably much more sophisticated methods to achieve this result, but the above are both implementations I've run across.
My software drops breadcrumbs within the users system which is used to check for previous installations. This is a little harder to get around (assuming you don't know what you are looking for, or where) than an internet check against your IP. As you can always spoof your connection information, or just disconnect from the internet while installing.
How can I determine which processes are making changes to which files.
I did find this:
FileSystemWatcher: how to know which process made the change?
But I'm curious if anything has changed lately? Is it possible yet to determine which process is making changes to the file system, either using ReadDirectoryChangesW or anything else? I'd prefer not to have to write or use a kernel driver.
Create a security audit on the files you want to track. The information will be recorded in the security event log.
While it may be possible to find out the process that changes a file using kernel drivers (for example, process monitor), there will always be a problem identifying the process in case the folder is shared on the network, and a process on another computer modifies the file over the network.
Even the kernel drivers would in this case identify the network share process as the one accessing the file, not the process on the other computer.
I can't seem to comment yet. I would be interested in your Python code that creates a security audit on files or paths. It's a bit of a shame if it messes with the system security event log, but you can't have everything! :-)
Up until this point, I have been using GetForegroundWindow at the time of the change to eventually get the associated process. It only works well for changes initiated by the user, but that is primarily what I've been interested in. Besides background processes, the only minor issue is that sometimes a process is spawned just to accomplish a task (like a batch file) and it is non-existent by the time you want to learn more about it (like what process spawned it). I imagine that is a problem even with a security audit, though.
I've run into this problem before and the solution has usually been to restart IIS. Basically I've made a number of changes to a .wsc file on our server. But when it runs it doesn't run the new code changes I made. I've verified this with event logging at the beginning of the file and it doesn't show up.
My problem is that obviously restarting IIS on our production server is something I'm loathe to do, but we need this running today. I've tried re-registering the file but to no avail.
The server is a 32-bit Server 2008 OS. And the code is running, it still generates the file it is supposed to, but like I said, it's not using the latest changes.
Any other info I can provide, please leave a comment and I'll edit.
Thank you,
Jeff
Edit: Oisin, thanks for the reply and yes I know I hate VBScript, and anything related to it including these Window Script Components. I've expressed such feelings to my manager, but it's a dirty job and someone has to do it!
Yes it's using a Server.CreateObject to call the component.
ANSWER: I've since realized my mistake. I was only 'registering' it over and over, when I should have first 'unregester'ed it the 'register'ed it. Man I feel stupid, but haste makes waste as they say.
Thanks for the response and link!
Eek, you mean WSC as in a Windows Script Component? I haven't written one of them since 2000.
Are you loading it using CreateObject (e.g. it's registered as a COM object via regsvr32), or are you using a file-based moniker to load it? (not registered).
If it's registered, it probably is cached until app restart. If you switched to a file based moniker, e.g. like: Set o = GetObject("script:c:\path\obj.wsc"), you might get away with runtime changes to the .wsc file.
(man, how did I even remember this)
more info here - quick before it's archived! :D
http://www.microsoft.com/technet/scriptcenter/resources/scriptshop/default.mspx
-Oisin
An application is hanging occasionally, and I would like to see the dump at the time to figure it out. I had written an application that the user can run to automatically create a dump that I can look at. However I can't seem to get the users to remember to run it when it hangs, no matter what I try. They always end up closing the program, which invokes Windows Error Reporting.
WER will create dumps in the temp directory, but unfortunately they are deleted as soon as the dialog for sending the info to Microsoft or not is closed.
Becoming an ISV and getting this info from Microsoft's error reporting servers is one solution.. but not one that is realistic at the moment.
I can't imagine that I am the only one faced with this issue. The software is used concurrently by dozens upon dozens of staff, so reaching them all and getting them to run an application or not click close on that dialog until running some other application or etc has not been working out.
The app is running on Windows Server 2003. Too bad, since I know Server 2008 has some LocalDumps options that will let me retain them.
Any ideas for somehow keeping these dumps around so I can analyze them? The obstacle is the user, in the sense that I've accepted to their stubbornness and do not expect them to run any other application or do anything special.
Thanks for any advice!
You could opt for an automatic solution. I believe there're multiple options at your disposal for detecting if you're hung.
One would be the use of SendMessageTimeout (also pay attention to SMTO_ABORTIFHUNG as one of the fuFlags values) from a separate thread in your app. Once you have determined the main thread is not responding you can save a dump file wherever you want.
There's also a IsHungAppWindow() (user32.dll) available since w2k.