Cant use addons

[Meurum23]

I add addons to the addon folder, go in game and no addons nor do any type commands work. What am I doing wrong?

[Mitzen]

On character selection screen, at the bottom left you can see "AddOns" click that, enable desired AddOns, and tick that Load Out of Date -box.

No AddOns on that list? Go to your WoW/Interface/AddOns/ -folder, and check if the AddOns are packed within an extra folder. This is sometimes the issue when AddOns aren't showing up, despite being for the correct WoW version, and installed within right folder.

E.g. they might be installed like this:
WoW/Interface/AddOns/DBM/DBM
WoW/Interface/AddOns/DBM/DBM-TBC

When they should be installed like this:
WoW/Interface/AddOns/DBM
WoW/Interface/AddOns/DBM-TBC

and so on.