I got to about 81 in Smithing naturally but then got the O.I. so used the exploit to get to 100. This also allowed me to complete the Smithing perk tree.

I still get the 'you do not have the required skill' when I try to improve some items. I thought that at this point, all the perks and skill at 100, I"d be able to improve anything to its max level, but can't seem to.

I have no idea if I messed the game somehow by using the O.I exploit or if there is some allied perk I need to get or what's up here. I can potion up (when I find the rare blacksmith improvement potions), but my competed perk tree and level 100 in Smithing seems not to be enough.

Frustrating for me is this *#&#& error message. I wish the game would tell me WHAT I'm missing rather than I get this *#&#& message over and over again throughout this game.

So what do I need to NEVER get this message again until, of course, max out the quality of my armor and weapons?

What are you trying to improve?

With all the Perks you should be able to improve the corresponding gear.

I've never used the OI for anything other than Magic (because I don't really use Magic - a little Illusion and Dead Thrall on my Assassin to be impish, but not for true fighing) and everything I've tried/used in the Magic schools has worked fine.