Ok, you're not the only one with this problem.
EDIT: found the solution, apparently it was thanks to Photoshop messing up with the filename extension in the registry causing this problem since as some of you might know, 3DS is a filename extension for some Photoshop files. To fix this problem, go to
HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Explorer\FileExts
And try to find 3ds (it should be at the top). Click on it. Once done, proceed to check the OpenWithList And the OpenWithProgids menus for all strings related to Photoshop, then proceed to delete them. If you have a problem during this step, just look at 3dz, and compare it with 3ds. Both should have the same strings and keys.
The registry entries for 3ds and 3dz are exactly the same for some reason