Now this might be a stupid question and I'm just forgetting something. It's been such a very long time since I've played this game. But when I rest (I'm just at the start of the game so that means spending the night at the local inn) the mages in my party aren't getting their memorized spells back. The cleric, the paladin, the ranger, they get their powers and spells but the mages selected spells show up in the spell book as the memorized spells but in the casting bar they are grayed out. It's this way for the mage in the party and the fighter/mage as well.

Take the armor of your mage/fighter and Mage. Only Robes are OK. Or Install IWD Tweaks.

In fact, if you ever played BG2 this would be the first thing you will notice when you equip Imoen with a Leather Armor, much hilarity insures. Theres mods that remove this restriction and you should install them, as Armor does in fact, also add a chance your spells fail so its still balanced.

Besides that i know of no (other) reason why casting is greyed out.

Ah of course. It's been so very long since I've played 2nd edition or BG/PST/IWD that I forgot completely that multiclass fighter/mage or mage/rogue cant wear anything but cloth. I already use the tweak mod but I selected not to install that particular part, I may change that.

Thanks :)

The one thing about the spell-fail mod that I didn't like is that it had penalties for wearing helms and shields as well. I know this is true to spirit of the rule-change (and I think it is only a 5% penalty for the helm and a 5% or 10% for the shield), but It still bugged me. It is not THAT hard to get good mage robes and/or bracers (in either BG1 or BG2), but it really sucks to limit the use of some of the helms and shields (especially for cleric/mages). Just my take on it, ymmv, obviously.

EDIT:
Just to put a finer point on it, my Cleric/Mage finished BG1 with a -7 AC, which is pretty dang good even for a warrior. That is with the best items in the game, of course (my two fighters only had around -3 AC or -4 AC, but my character was a selfish Law Evil type :P), but it shows that the mod is hardly necessary. I would only use it if you are used to, and like, the way 3rd Edition handles armor and spell-fail.

EDIT2:
Oops, I forgot which forum I was in. I should have wrote that my cl/ma in BG1 finished the game with -7 AC. Icewind Dale has different items, but most of what I wrote still applies to IWD.