One last thing, I don't do the conventional upgrade. This might not be recommended practice, but it works for me.

I get a brand new build and copy all the portals across from my old install except default portal. I then use BEYOND COMPARE application to compare the difference between the default portals and selectively copy/delete, I'm sure there are other apps that do something similar (let me know if there are any free ones :). Also there is quite a lot of gunk I can clean out of various portal folders so I do this there and then.

I run the installation, and I get a load of errors with the missing modules and I resolve this by simply installing them. This also gives me the oppertunity to update my third party modules to the latest versions. It also keep things nice and clean with the build.

It takes time, and isn't exactly plug and play. But it works if you have full access to the server. In fact I don't. I copy all the files + database down and copy them all back up again and check for any changes afterwards. Of course this gives me a few hours of downtime which might not be acceptable in certain situations.

Hi,

I find that doing an upgrade only works when going from 4.3.5 to 4.3.7 worked well.  Otherwise I've always run the install version against my sites with no problems.   I did run an upgrade from 4.4.1 to 4.5.0 and did have issues, so restored a backup and ran the install and everything worked just fine.  When the 4.5.x is released, I plan to run the upgrade.