@Robert
Thank You very much for clarifying.
Reading the Symantec description supplied by Your link about Suspicious.Insight turns my doubt towards zero.
Quota from Symantec´s site regarding Suspicious.Insight:
... When detections of this type are triggered in Norton products the user may be warned that the application is unproven, thus allowing the user to make the final decision ..
... The warning typically indicates that the file has very few users or is very new, and therefore has not developed a reputation.
... Symantec recommends software publishers ... Digitally sign all software application binaries.
...Software developers who want to accelerate the reputation building process for their new software applications should submit new applications to the Symantec white-listing program.
Quota end
So I learned: before posting to this forum, I should have checked Symantec´s site for Information about Suspicious.Insight. This would have been the easier / time saving way ...
Advantage for 'Hijack Hunter' from NoVirusThanks.org: Now it has a better reputation

Finally I can devote to my original problem (my first post), the USB Memory Stick, which is probably corrupted. The OS wants to format it on each access. First I will install and run 'Hijack Hunter' to inspire my system. By the way, Robert: Many thanks to NoVirusThanks.org for providing such a powerful tool - for free.
@All
Thanks and have a nice time.
Regards,
DoobieBrosFan
[Spirit, 1974]