For this reason, we need to whitelist Synpse install folder in windows defender for Synpse to work. Particularly this is blocking the auto-upgrade feature.
How to exclude synpse from Windows Security checker?
Search for "Windows Security" in the Windows search bar:
Go to Virus & threat protection ->Under Virus & threat protection settings, select Manage settings, and then under Exclusions, select Add or remove exclusions. Select Add an exclusion, and then select folders and add C:\Program Files\Synpse
This is the main folder where Synpse will create a temporary agent file and do in-place upgrades