I'm having this issue where when i use the paint brush tool or the eraser tool, instead of erasing it moves the line. sometimes it will erase and sometimes the line will be moved. but when i zoom out and then zoom back in either the line will be back to normal or it will be erased like it should be. the same thing happens with the paint brush tool where if im trying to draw over the same line i have a similar issue. sometimes the line im trying to draw over gets moved or sometimes it just adds a bunch of white pixels. ive done everything to try to fix this. Ive restarted photoshop, updated all my drivers, and even uninstalled and reinstalled the program.
when i tried to go to a previous version to install it says there were files missing and to uninstal it again. i have no idea how to fix this and its really getting in the way of digital painting. Here is a video that kind of shows the issue. at first you will see that it is erasing normally and then all of a sudden it looks like it starts glitching.
Try resetting the tools and/or preferences. To restore preferences quickly using a keyboard shortcut:
Press and hold Alt+Control+Shift (Windows) or Option+Command+Shift (Mac OS) as you start Photoshop. You are prompted to delete the current settings. The new preferences files are created the next time you start Photoshop. Note: Using the keyboard shortcut, preference files for custom shortcuts, workspaces, and color settings will also be reset to default.
The video is small and moves around the screen very quickly. I can't tell which pixels are on which layer. You might (or might not) be trying to erase pixels that are on a different layer. Can you hide all layers but one, then try? Then repeat with another layer selected and visible.
You might also try resetting your brush and eraser tools before restoring all preferences. Right-click the Eraser tool in the options bar (not Tools panel) and Reset tool. Repeat for the Brush tool.
Before I was convinced there was a problem, I'd need to see the erase used on a document with just a single layer with lines drawn onto transparency. So that we can be sure that the erase is not simply revealing what is on a layer further down the stack. Which is what Jane is aluding to.
Having said that, I have had an issue with the eraser tool in the last few days that was fixed by reseting all tools, so definitely try Bob's advice. We hate suggesting people reset Preferences unless all else fails, but there is no down side to reseting tools, so I always reset All Tools when I suspect things are not as they should be. Note this is not always Photoshop's fault, but can be where we have messed up different settings to the point where things don't work properly.