I have written some macros (Excel) in W7. Work perfect on multiple devices - W7 & W10.

 

When file is opened in XP - those are working only once and deactivated after second start.

 

Launch from external USB - works with few openings. Copy to desktop - works. Next reboot - works. Next reboot - "macros deactivated".

 

Scenario is replicated on laptop and desktop with the OS being installed independently from different distributive.

 

Permissions are maximum - i.e. "allow all macros"

 

Tried to add digital signature via SelfSert - same results.

 

Microsoft site does not give much (only talks about selfsert).

 

Ideas? Need to understand where to look to avoid that backwards incompatibility. Need it to work on XP in other words.