Troubleshooting "Cannot access a failed instance" on PST export

[Rob Clarke]

Hi,

I'm looking for some troubleshooting advice on an error while trying to perform a PST export on a Exchange 2010 server.  The export process starts ok and gets to about 70% and then bombs out with the following error:

"Error: \\servername\Export\username.pst --> Cannot access a failed instance"

It appears that the process has lost ownership of the PST file it was creating.  I'm going to check there is nothing running on the server that might affect this i.e. server backups, AV scanning.

The end of the report file suggest corrupt items, however this appears to be the same time the PST is no longer accessible and may be a result rather than cause.  The corruption errors are all have the same timestamp seconds before the export process fails.

Thanks 

[#2 · Accepted solution]

Just for reference.  The issue was caused by AV scanner grabbing the PST while it was being built.  Excluding the folder where the PST files were being exported to fixed the error.

I've added this to my blog here