I just reinstalled FO3 the other day, after playing my heavily-modded copy of Skyrim for the past year or so. However when I tried to mod Fallout, right from the start I was getting problems.

First, I installed FOMM and FOSE and tried to use that, but it would freeze and/or crash every time I clicked "Packet Manager" and tried to sign in. After giving up on that, it would freeze when I just tried to add a mod by clicking the button.

So after getting sick of FOMM I reluctantly tried NMM, which got ONE mod installed, which was FWE but has been giving me problems trying to install other mods.

For example: I tried to installed Mart's Mutant Mod, but upon installation it would ask me if I wanted to overwrite a bunch of FWE's files. I clicked yes and things went okay until the very end. I kept getting an error saying that a FWE file was missing and the mod could not be installed... Even though I was installing MMM. Then it said an MMM file was missing when I tried to install FOOK2.

My game worked perfectly fine with just FWE installed. Everything was great. Except I couldn't install any other mods.

I just installed Fallout 3 and got rid of everything Fallout related before I did. So starting fresh... How am I supposed to make this work??

Not sure what advice to give, but I also reinstalled FO3 the other day and have had no issues whatsoever with NMM (which I use as the default installer), FOMM (which I use for a couple of mods and archive invalidation) or Wrye Bash (I use BAIN for some mods as well as the Bashed Patch). And the game has been extremely stable as well, at least after using the 4GB adress enabler - in fact, I haven't had a single CTD so far even if I use loads of texture replacers, FWE, MMM etc.

My only issue is that if I install EVE, I don't get the menu for loading saves etc. on the start up screen so I can't use it. Weird issue, but I haven't looked further into it yet.

Hmm, weird. Well now since I installed Fallout to my second hard drive NMM doesn't seem to want to recognize it.

I get that as well, but if I click "cancel" I get the Packet Manager window and can activate/deactivate mods w/o issues.