Why is X1 saying it can't access my .PST file?

Worryingly, under Outlook email options there is an option to "Ignore alert for unavailable PST files".
It's tempting to tick this however I don't want to tick this as if X1 is genuinely failing to index my data I need to know.

Or is this a clue that there is a long-standing buy that X1 can't fix ??!!

J

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