Warning - Missing Audio Data Block Files

This warning message will be shown when you attempt to open an Audacity project which has audio data missing for some reason.

and in context

With silent gaps showing

Very easy to get this problem when working over a network or using removable media.

• Disk errors could also be a cause.
• Overly aggressive security / system maintenance products could cause such problems/
• User errors have been known (users messing with the contents of the _data folder).

and the log file

Peter 29Dec19: the raw out of context warning dialog - but I think I prefer the in-context one