Spirono,

I have not heard that uninstalling Edge would cause the system to be slow opening websites. Have you installed Chrome or used Internet Explorer in Windows 10?

Apologies - I uninstalled W10 - I didn't try but believed that uninstalling Edge would not be possible. You could not deselect it as the default to open PDFs and links.

I did realise that I could try Chrome rather than Explorer earlier today but EBay runs fine in Explorer as I type and it certainly runs fine in Chrome at the moment too - I prefer Explorer though - old habits.........

The warning from Avira that I am trying to run something from a location that does not exist, still appeared at switch on though.

Did you install Adobe Acrobat or Reader first before trying to change the default program for pdfs?

It is possible to use another program by going to Settings -> System -> Default Apps, go down to 'Choose default apps by file type'. You can then change the default for pdf files.

Acrobat had been on my machine for a very long time. If you tried to make it the default for PDFs, you could not untick Edge, as you could not untick Edge for a few other things, such as opening links. This is why I uninstalled W10.

P.S. I forget the entire list of functions for which W10 sets Edge as the default, most I could and did deselect, but not PDFs or links.