For those who are saying no problem here or words to that effect (other than Pondus), are you using the MBAM Pro version as the OP is. If not then you aren't able to replicate this if there is no MBAM resident protections enabled.
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Was done when the fp warning window opened.
The path also is entered in the general exceptions to Avast.
A Quick Review just did not reveal any other rootkit message.
What FP warning window ?
I assume this is the anti-rootkit scan about 8 minutes after boot which detects this, if so that doesn't follow the general exclusions (on-demand scans only) as far as I'm aware.
A Quick scan, doesn't launch the anti-rootkit scan, that is only part of the Full System Scan (or custom scan), so that I would say is why there is no rootkit detection with that scan.