Run Windows 7 Error-checking, with "Scan For and attempt recovery of bad sectors".
This means the file was physically damaged.
If I get Outlook Running, should I move old messages to separate PST files, a year at a time?
I use Archiving. I have email back to 1996 and only a 1 GB main PST file. You can move emails to separate PST files, but Archiving does this automatically.
The maximum size of an Outlook 2007 file is 20Gb; the maximum size of an Outlook 2013 file is 50Gb. So the newer version can handle more email.
However, very large PST files tend to slow down Outlook and Archiving is one excellent way to prevent issues.
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