"Scan complete. THREAT DETECTED!" but report is clear

Avast Free Antivirus / Premium Security
1

A quick scan displayed “Scan complete. THREAT DETECTED!”. The “Show results” button depresses but does nothing and the scan history shows the scan finished with “no virus found” and 0 infected files. Am I safe or not?

2

Please use the search option before posting since this is already explained many times.

3

https://forum.avast.com/index.php?topic=154583.0

4

Thanks Pondus.