Whenever I try to exit the Sewers, I get this message, "I cannot go that way. I should turn back." After doing some research, I found out that it's because the bBorderRegionsEnabled is set to 1. I went into my Oblivion_default.ini and set bBorderRegionsEnabled=0, but that still did not work. So I installed borderlesscyrodiil.esp and that didn't work either. I recently installed a huge batch of quests mods and rebuilt the bash patch.

Here is a list of the new esp's I installed:
DarknessHollows.esp
DremoraCompanion.esm
DremoraCompanion.esp
ElsweyrAnequina.esp
ElswyrC&CBlackwoodPatch.esp
faregyl.esp
Faregyl+Anequina Patch.esp
Feldscar.esp
Legion Faction Mod.esp
Malevolent.esp
The Buther.esp
TheForgottenRealm.esp
TheOubiette.esp
TotF.esp
TR_OoT_Main.esm
Windfall.esm
Windfall.esp

You edit oblivion.ini in My Documents/My Games/Oblivion/. You don't ever edit oblivion_default.ini.

Edit: Wait a second, you get that message exiting the sewers? Something definitely isn't right here.

That did the trick, thank you.

The "turn back" message happened because two or more of the mods you installed edited the border regions. When that happens, it all gets blown to hell. The only reliable way to do this is to use the ini edit you've applied.

I see the ESM for Stirk/Hammerfell, so that's one. If you're using OOO, that's the other. Boom. Borders broken. There's a reason why some things should never be edited