First things first. I work with the following setup : win7 64bit, photoshop cs5 (latest update), wacom intuos4m (driver up to date). I don't do a lot of drawing in photoshop, so I may have missed the exact moment when the issue started, but yesterday I got annoyed. I was drawing and then flipping to use the "eraser" end of the pen, it didn't work, it simply continued to work as a brush. I remember it working fine last year, so I checked the software setting of the pen, first. They were still ok. Then I went to Wacom forums first where I found this :wacom.eu/viewtopic.php?f=2&t=8324&p=34735&hilit=eraser#p34735, The state it's the software that handles the pen, not the wacom driver, so therefore the glitch must be photoshop's (according to wacom). So I did reset photoshop to it's default, but it didn't change a thing. The eraser end of the pen is still not working. Further googling didn't reveal anything useful. Anyone who ran into the same issue and found a solution ? It's a habit of not switching to??.
I didn't find the right solution from the internet.