That is what I thought with this being a .dat file. It looks like a false positive detection.
If it is indeed a false positive (and it would appear so), add it to the exclusions lists (
Standard Shield, Customize, Advanced, Add and Program Settings, Exclusions) and Restore it to its original location, periodically check it (scan it in the chest), there should still be a copy in the chest even though you restored it to the original location. When it is no longer detected then you can also remove it from the Standard Shield and Program Settings, exclusions.
Since you have a sample of the file in the chest, you can send it from there (select the file, right click, email to Alwil Software). No need to zip and PW protect when the sample is sent from chest.
Don't change any of the default settings in the window that pops-up, give a brief outline of the problem (possibly a link to this thread) in the Additional information text box and the fact that you believe it to be a false positive
Also see
False Positives, how to report it to avast! and what to do to exclude them until the problem is corrected.
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