The performance monitor showed so many files being accessed it was hard to follow. The Origin.exe on it's own had more rows in there than fit on my screen.
Anyway, based on what I saw I set quite a lot of exclusions in both \AppData and \Program files (x86) but they all didn't help much.
So I just tried excluding c:\ which also didn't help.
Only after turining off "General", "Exploits" and "ransomware" in Sophos Home under the protection tab did the update work.
Didn't get to play the game though, too much other stuff to do this weekend :-)
I have a workaround that works for me. Hopefully someone else will benefit too.
I have Sophos Home too and cannot see any logs or events that would indicate that there are issues with it and the writing of the updates into the executables etc.
What I can see is when I leave the Star Wars Sqaudrons folder open, I see the DIP_STAGED files and other files that appear to be the actual patches before they are integrated into the DIP_STAGED file. Once I receive the first retry error in Origin, I go into the folder and delete any original file that now has a DIP_STAGED equivilent file. I then rename that file and remove the DIP_STAGED. I do this for the entire folder structure where the game is installed (not the program files etc).
Once I do this, I click the retry and it will resume the patching and probably stop at around 98% with yet another retry error. I go through the folder structure again looking for DIP_STAGED and delete originals and rename the files.
I often find that the touchup.dat and cleanup.dat originals are not present but their DIP_STAGED files are, I think this is part of the problem but who knows.
Anyway, after multiple retries, and lots of renaming, I get the update to finalise. Once this is done, I run a repair and can run the game again.
November - last edited November
@zoufrInteresting. I didn't do anything with the AMSI scanning option, because I didn't think that the Origin Installation System would be using integrated scanning. One more thing I'll pass on to Sophos. 2nd Level are still investigating, but there is a problem because once you succeed in updating you can't update again until the next update becomes available. Waiting for the next patch now.
Update: Just opened Origin and it started downloading an update. Looks to be the same size as the last one. We will have to see what happens.