App no longer working - any ideas

Question

I am out of ideas as to why my app has suddenly stopped working - perhaps the collective mind of the SO community can help...
Background:
I have a large application that has been working up until recently. Now when ever I try and run it I get the error "The application failed to initialize properly (0xc0000005)"
This happens before the app gets to _tmain(). It happens in both release and debug builds. I have tried cleaning and rebuilding the projects and rebooted my PC.

The call stack just shows entries for kernel32.dll and ntdll.dll
The output window shows:

First-chance exception at 0x00532c13 in a.exe: 0xC0000005: Access violation reading location 0xabababdb.
First-chance exception at 0x7c964ed1 in a.exe: 0xC0000005: Access violation.
Unhandled exception at 0x7c964ed1 in a.exe: 0xC0000005: Access violation.

Any ideas?

Edit:
Okay - found the problem - it was dll related
my app uses shared dlls a.dll and b.dll (and others)
a.dll hardly every changes (and uses b.dll)
b.dll was changed by another developer this morning and a.dll was not rebuilt.

Depends.exe did not show any missing dlls, however a.dll no longer works because of the change to b.dll

Answer 1

Check permissions?

Answer 2

Maybe an windows update messed with the system.

Answer 3

What is your platform?

What language is the application written in?

Did you install any updates or other products recently?

Answer 4

There's probably some .dll file that is required for the application, but it's not found, or access to it is not allowed.

Are you using some dll's, or maybe some runtime library of any kind?

Answer 5

This link seems to describe three issues as possibile causes:

• Data Execution Prevention
• Driver or system update
• Faulty Ram

details here: http://www.updatexp.com/0xC0000005.html

let us know if you find the reason

Answer 6

Have you perhaps used SysInternals suite to examine what's happening? This would help you pinpoint any failure for instance if it's accessing a file, DLL or a registry entry and access is denied.

Does your program work fine if you install it elsewhere? (another computer) That might help isolate the issue.

--You could check are the event log (application, system, etc) to see if anything is getting logged about the problem.

--Another thing... Since you updated Tortoise, perhaps it uses a DLL your app also uses. You should check to see if any DLL versions have changed. You could uninstall that newer version of Tortoise. Or more drastic, try a registry restore. (http://support.microsoft.com/kb/322756) Or if you use Ghost/Acronis restore to an earlier image of your OS.

Lastly I'd recommend trying to be very specific at finding out what is wrong. I mentioned some drastic measures in fixing the problem, but hopefully you can specifically (i.e. DLL ver x causes the issue) narrow it down. Otherwise, It would stink for a client or user of your application to run into the same thing.