John Dow

I'd suggest checking it with your local ESET distributor as it concerns legal matters. As far as I know, using a single license on a multi-boot system is ok.

ESET NOD32 Antivirus, ESET Internet Security and ESET Smart Security Premium version 15.2.17.0 have been released and are available to download.
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Version 15.2.17.0
NEW: Anti-Theft optimization page in the product NEW: Network Inspector: possibility to categorize own networks as “My network” FIXED: Outlook plug-in does not scan the Junk folder any more Bugfixing and other improvements Known issues:
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Thanks for the heads-up, we'll investigate the issue and do our best to make portable applications run without the need to create exclusions.

It seems the problem was due to "Deep Behavioral Inspection" in HIPS
I added the "portable" folder into the Exclusions and it seems to work regularly now
I'll come back if some other problems arise