Some of you might have experienced this already.
There is a SPR with the same title: SPR 1190832
It mentions it will be implemented in 2020 sp5
Simplest workflow to see the problem:
Create a new part and save.
Create an assembly of that part and save.
In the assembly go to pack and go -> SolidWorks crashes.
Save your files and use the pack and go via windows explorer.
Doing the same in solidworks 2020 sp4 works without a problem
I don't know if uninstalling 2020 will solve this. Has anyone done so? would be interesting to know.
So, for anyone thinking to update to Solidworks 2020 sp4 and use it for production:
If you use P&Go a lot from Solidworks and don't want to use the workaround via Windows Explorer, wait a little longer for Solidworks 2020 SP5.
Hope this helps someone wanting to make the update...