Edge browser downloads files as .txt & other problems.

Edge browser worked fine a few days ago but today I had a major headache with it, first any program I downloaded refused to download, if I retried it downloaded a .txt file, choosing 'save as' only gave me text as an option.
Two: Non of my extensions now work, nothing happens.
Three: Upon opening the page crashes & reopens.
Do I need to reinstall AU or is it a wider problem?
I use IE usually but was getting used to Edge.
I have run sfc & no problems found. Also run chkdsk & ok there.

Hi, Do you have any usable system restore points?
Have you been using disk imaging (as is very strongly recommended here)? If so, can you restore an appropriate image?

It sounds as if several things may have gone wrong. If neither of the options above is available, you might just try an in-place upgrade repair install (basic information in the Tutorial section).

Yes to both. Am currently trying a system restore. Will post back with an update.

Update: system restored to 4 days ago problem still occurred. Ran AU reinstall & all OK. ��

Ok, keep a simple of log of any changes you make, watch for any recurrence.
Meanwhile, start using disk imaging so you've a base image starting with a working configuration you're happy with.
Macrium Reflect (free) e.g. + its boot medium + storage for image backups

Already image & clone with Macrium, latest image was a day old so had the problem, previous image was pre AU, as I'd have to download AU again I thought in-place repair would be the better option. Fixed a couple of other minor niggles too. :)
I suspect what caused it (a temp file cleaner recommended on an well known anti malware program site for helping with problems with their product) & will keep well away in future.

Great!