Did you try to give the full path of the command that is running in the pre- or post-build event command?
I was getting the 9009 error due to a xcopy post-build event command in Visual Studio 2008.
The command
"xcopy.exe /Y C:\projectpath\project.config C:\compilepath\"exited with code 9009.
But in my case it was also intermittent. That is, the error message persists until a restart of the computer, and disappears after a restart of the computer. It is back after some remotely related issue I am yet to discover.
However, in my case providing the command with its full path solved the issue:
c:\windows\system32\xcopy.exe /Y C:\projectpath\project.config C:\compilepath\
Instead of just:
xcopy.exe /Y C:\projectpath\project.config C:\compilepath\
If I do not have the full path, it runs for a while after a restart, and then stops.
Also as mentioned on the comments to this post, if there are spaces in full path, then one needs quotation marks around the command. E.g.
"C:\The folder with spaces\ABCDEF\xcopy.exe" /Y C:\projectpath\project.config C:\compilepath\
Note that this example with regards to spaces is not tested.
If the script actually does what it needs to do and it's just Visual Studio bugging you about the error you could just add:
exit 0
to the end of you script.
Check the spelling. I was trying to call an executable but had the name misspelled and it gave me the exited with code 9009 message.