I recently bought an inexpensive graphics tablet and installed the drivers, plugged in the cables and off I went, everything worked perfectly. Then, I restarted my PC and now Photoshop is the only program that won't work on it. I click on the screen and it will automatically deselect the program. The pressure sensitivity on the tablet works on every other drawing program i have, so I think it is just photoshop I am having trouble with. I am running an old version of photoshop which could be the issue, but I just don't know where to start with this problem. I just noticed when I open the file viewer on that screen, the cursor is flickering. I'm trying to draw a comic book and this is the type of thing that really ruins my momentum. Any help would be appreciated. Thanks.
Older versions of Photoshop were actually less problematic regarding pen pressure, than CC 2014 and later. We don't know what operating system you are using, but this help page from the forum's overview page might help.