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Yes, the key words are “A suspicious hidden object” and “this may be a sign of malware infection.”
Allied to that is the recommended action to Ignore.
Truecrypt’s driver must be running at a very low level to be able to encrypt on the fly, though why it is hidden is beyond me.
Open the advanced options and see if it allows for a) reporting as a possible FP and b) ignoring in the future, but there would be an element of risk in that.
I’ve manually chose to ignore… The default was delete!
Can’t do that anymore… once the dialog was closed…