Needs elevation (the usual fix doesn't work)

On a Win7 ultimate system (svc pack 1), when I try to open any file in the my documents folder I get an error message that says that this operation "needs elevation".

So I picked one particular file that I couldn't open and I looked at the owner in the security tab. Indeed the owner was not set to me. It was set to "Administrator". Although I'm logged in as an administrator, my login has my name in it, so this was not me. (I don't see any other user accounts however). So anyway I go ahead and change the owner to me. If I cancel and go back in thru properties I see that this worked. (i.e. I am now listed as the owner of this file). However windows still will not allow me to open the file (same error messages). I have the permissions set to "Everyone", and all the permissions are checked. (I do this to allow full file sharing, even with non Windows 7 computers). I've tried playing with various permissions, but everything I see is checked. Why is windows still so insistant that I shouldn't open this file?

By the way, I tried copying the file to another drive. Windows allows that, but again I can't open it. Then I deleted this copy, which windows did without complaint. I'm dumbfounded. Windows thinks it's perfectly acceptable for me to have rights to delete a file that I have no right to even look at.

By the way, I have run Malwarebytes and Superantispyware. Both found and fixed a few problems, but still this needs elevation problem remains.

Thanks in advance for any suggestions you may have.

~Paul

I thought I should add that I just tried changing my "User Account Control" to the lowest notch (never notify). However I still get the dreaded "Needs elevation" warning just the same.

I also verifed that the files in question are still good. I can copy these files to another computer and they open just fine there.

I hope there is a solution short of reloading the operating system, since that will be painful and quite time consuming.

~Paul