Rubbing alcohol on a lint-free cloth ... like the cloth sold to clean eyeglasses and computer screens.

Did someone pop open a can of soda in front of the TV?

I've 'experienced' that before.

One more vote for the alcohol.

I grab a used dryer sheet, and use that to run over dusty TV and computer screens.

Any advice that involves the use of any mixture containing either ammonia or alcohol is bogus or obsolete. Always shut off the unit and use a real Microfiber cloth, or well worn piece of clean soft cloth. The cloth should be dampened with distilled water, and wiped very gently from top to bottom with the TV turned off while exerting minimal pressure against the screen. If that doesn't work, buy a brand name cleaner made to deal with the problem at Wal-Mart or similar outlets.

I agree with laat2

You cannot clean LED screens like you did with the old analogue TV screens If it doesn't come off with a damp cloth or a microfiber cloth then use a cleaner designed for it. You could ruin your TV using alcohol

My instructions said do not use any chemicals or cloths with chems in it. They suggested a soft dry cloth. Your spots could be cause by something inside the TV.

I just popped back in this morning to check this.

I need to dig out the owners manual. It's a Sharp Aquos. When we first bought it, two years ago now, the first time I ever dusted/cleaned the screen I used a regular microfiber cloth and water. The screen was fine but DH informed me it came with a special pink cloth for dusting.

Thankfully the marks are only noticeable when the tv is off and you're up close.

Thanks for the responses. I saw they make cleaners for LCD screens but I've read some bad reviews for them too. I'll post an update of how I make out. I'm not sure what I'm going to do if mine also says to use the dry cloth it came with since that wasn't cutting it.