Issues with Guards, On numerous occasions now... Options

[Burnt]

First time I was doing a Thieves quest, got caught, no biggie. Off to Armand to pay off my bounty, done. NOT. They're still chasing me, etc etc. In the end, I had to load up a saved game from awhile back and do the quest all over. Not too bad, it wasn't a hard quest.

Now this, I'm in the "Big Heist" quest now. I got into the palace, but as soon as I appear in the room, a million guards are aware of me and attack me, needless to say, this ruins the quest. So I figure, next time, I'll wait until the middle of the night to go in, when they'll be asleep, nope. They're all still going nuts attacking each other, an innocent person and me.

I searched for some Thieves Guild help to no luck, so any suggestions on how to get around this "glitch" or issue, it would be very appreciated. Thanks everyone.