This is very likely a doofus question but I will explain afterwards.

Do you have to use the release.config (modified with proper connection settings and machine keys) as the new Web.config for ALL upgrade from version to version?

My problem is that when I updated one portal from 4.9.3 to 5.01.00 I got the usual and expected error about hte Event Log update as others have posted about. I used the modified release.config and in general the upgrade went okay. However when I would try and upload a new version of a module or and other type of submit action I would get a general exception error. I did a manual run of the 5.01.00 sql and it ran and updated as it should.

I decided to try the 4.9.3 web.config file and the site works without any errors. I even updated the event module without issue.

I tried to use the updated release.config and it will cause the site to not load at all with the Resource not found 500 error.

Any ideas would be great before I begin updating other sites.