I have now tried 4 different HTML editors and none of them will not accept the code directly from PS. (Coffeecup, CuteFTP, HTML kit, and PageBreeze) One of them even gives me an error window that says "Clipboard Error".

Obviously this is some weird incompatibility between Photoshop's "Copy CSS" function and raw code HTML editors. (of course on the PS boards they are saying it can't possibly be the fault of PS)

Hopefully someone who knows the back end of Coffeecup can shed some light as to why this might be.

Well the fact that it's not isolated to CoffeeCup is telling you and PS that it's in their program. This is not an HTML Editor issue it's a PS issue and needs to be addressed on their end. They can't expect 4+ (I say plus because if there are 4 then it's most likely most of them) programs to adhere to their setups, they need to address it.

As for the copying and pasting, I think you misunderstood. I wasn't talking about what you paste "to" Word or Wordpad type programs, I was talking about when you paste "From" them to any web building program that you run the risk of adding extra characters to your web pages. That has been the case for years over multiple HTML editors and wouldn't be different when taking things from an image program or any other. Programs that aren't raw text have the tendency (not always, but many times) to add their own special hidden characters into your code that you cannot see.
Trust me, it's happened to me many times before I finally learned this lesson the hard way. Hours of searching to find an issue that's almost impossible to detect is not worth worrying about if you're pasting the code twice. You should be doing that anyways is all I'm saying.

Granted that doesn't make the problem right, the issue is still there with PS not being able to paste into raw HTML editors, but that's on their end not CoffeeCup's or any of the other HTML editor developers.

Hope that makes more sense, and if they won't take responsibility, there's not much else you can do as it's definitely on their end. It's not something CoffeeCup can or should try to fix as that would be having to conform to a single software's idiosyncrasies which could constantly change and aren't a standard thing.

I don't disagree it's on their end but I am trying to cover all of my bases at this point as it's damned annoying to not have the programs working together to do what they are supposed to be doing.

Chances are that neither PS nor the Editor is at fault here but, rather, some other program or background process that under certain conditions may be deleting the content of the clipboard.

In order to try to isolate the problem, have you tried rebooting and then loading only PS and the Editor? Also disable any aftermarket utilities (aka "aftermarket junkware"), virus protection other than MS SE, 'memory managers', Skype "click to call" and any other superfluous processes.

It's not deleting the code, it's just not pasting into these html editing programs. It also does it on my laptop so it's not just this one incident. Basically I am at an impasse until someone involved in these products decides to just test it themselves and figure it out.

Over on the PS thread I keep getting this from a guy "Photoshop is putting text on the clipboard. Again, it works in other applications. Since Photoshop is already doing the right thing, we don't know what the programs that can't read the clipboard are doing that would result in them not being able to read the text on the clipboard. AGAIN: the developers of the failing applications need to debug it, and determine why they cannot read the text on the clipboard. "

They say it's your fault, you say it's theirs. Does anyone here have the newer version of Photoshop (CC) and can test this out as well?

Did you ask Microsoft?

I don't have Photoshop. I'd never pay that much for a program that I would seldom use. But I disagree with that person you quoted. HTML Editor, and I'm sure the other editors as well, are all reading the clipboard because we can copy/paste other text and graphics from other programs. The fact that we can't copy/paste from Photoshop leads me back to the conclusion that Photoshop is copying 'more' than standard text to the clipboard and it's these unseen characters or code that is causing the problem.

I disagree too but apparently he works on PS and claims it can't be them and seems to stand by the fact it's the other programs fault (even tho' it's been found in 4 different programs made by four different companies).

Also I have been looking around all over the web and no solutions are to be found, Microsoft or otherwise.

Until a solution is found, if ever, I have installed and am using CSS Hat which seems to be a better alternative to the PS CSS function as it's more visual, has better options, and best of all actually pastes the code into coffeecup.

Sounds like a good solution. Thanks for posting back with that link!