N360 uistub

I know there are other posts about this, but here goes.

My client has an Advent DT2 desktop with Norton 360 with wireless connection issues.  I thought I had exhausted my connection issues knowledge, until I read there may be a link between Norton 360 and wireless connection issues! 

I too get the message about UiStub.exe (the message is for 21.5.0.19).

I am going to download onto a usb drive, the remove and reinstall, but some questions:

Does it autodetect the version installed and just reinstall it?

If I can't get into the product, how do I save his Live Safe Data?

If no autodetection, how do I know which version to download and also his account information?