Email client on flash drive always blocked

I am running The Bat! Voyager email client from a USB flash drive (always allocated drive letter V:); I have tried defining it either as ‘Trusted Application’ or as ‘Email client’ but either way I always get a ‘could not be recognized’ popup at the point that it tries to connect to the mail server.

As a test comparison, I installed The Bat! (substantially the same program) on a local hard drive, connecting to the same mail server, and that works fine.

Any suggestions for a way round this? Am I missing something obvious?


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