Today I cannot open any files marked as .xls or .doc (97-2003 Versions) within Office 2010. This has only just happened and everything has been working fine up until now.
When I try and open a file the message
"The file you are trying to open........., is in a different format than specified by the file extension. Verify that the file is not corrupted and is from a trusted source before opening the file. Do you want to open the file now".
If I select yes I get rubbish displayed.
As I say this has been working fine. Also I have scanned the server and the PC with Malwarebytes and nothing detected.
If I restore the files from yesterday I can open them with no problem. I can also open all files created in the new version.
This is a shared network drive and doing a blanket restore will be a real problem. Why would thay have become corrupted and can I get around it without restoring the entire drive?