Occasionally my external USB hard disc is accidentially physically disconnected.

In the following time Windows seems not to recognize the whole situation and
tries to write some data resp. accesses otherwise the lost partition.

Because it cannot find it an error message window is popped up informing me:

"Windows was unable to save all data for the file \Device\MyData\$Mft. The data has been lost.
This error may be caused by a failure of your computer hardware or network connection.
Please try to save this file elsewhere"

Which file is Windows trying to save?

How do I permanently turn off this message (if I click the dialog window
appears 10 Minutes later again).

How do I enable Write-Through access for USB harddiscs (instead of caching the files)?