I have had the same problem. I did the various repairs suggested and sometimes it worked, sometimes it didn't. However, I have now found out how to make the problem go away, at least for me. Haven't ploughed through all the responses so someone else may have mentioned this, so I apologise now.
If I start Inkscape using my mouse, then try to use the app with my pen and tablet, I get no devices loaded/recognised, etc.
If I start Inkscape using my pen and the tablet and NOT the mouse, everything works fine.
I have had the same problem. I did the various repairs suggested and sometimes it worked, sometimes it didn't. However, I have now found out how to make the problem go away, at least for me. Haven't ploughed through all the responses so someone else may have mentioned this, so I apologise now.
If I start Inkscape using my mouse, then try to use the app with my pen and tablet, I get no devices loaded/recognised, etc.
If I start Inkscape using my pen and the tablet and NOT the mouse, everything works fine.