I'm having some weird issue that I've never experienced before after upgrading my machine. (I was previously on Windows Vista x86 with Photoshop CS3 x86, and I'm now on Windows 7 x64 with Photoshop CS5 x64.)
As part of my work I often have to take screengrabs of a website and paste it them into Photoshop. It's something I do without thinking, but for some reason I've had troubles since upgrading.
Going into Microsoft Paint and pressing CTRL-V reveals that the images ARE being stored in the clipboard, but pressing CTRL-V in Photoshop does nothing, and all the Pasting options in the Edit menu are greyed out. It's like PS isn't able to "see" the clipboard.
Any ideas why PS wouldn't have access to the clipboard? It feels like a permissions problem.