Dell Studio 1555 issues since Windows 10 update

hi all,

sorry firstly if this in slightly the wrong location, if so im happy to move or change it.

so; i have had my Dell Studio 1555 since 2009 and it was worked flawlessly since then, never a hiccup or issue. i got the warning roughly in Feburary to say Windows 7 would no longer be supported, so i decided id go ahead and update it. after updating it felt the laptop slowed down hugely, to the point sometimes where it felt it hung on simple processes.

about 5 days ago now i started my laptop, logged in and it gave me an error "we cannot sign you in... youve been signed into a temporary account" and no internet access (regardless of trying WiFi or using a cable). after 4 days of constantly trying to work out what went wrong, and almost 2 hours on the phone to Microsoft in Nigeria (one of the most frustrating conversations of my life), and a promised call back, noone called :(. 

after many tests and feeling like command prompt had been rinsed of all possible fixes, it was advised that the next step was to reset the laptop to its factory settings. after three times trying to do this (as the laptop would get a blue screen of death each time doing it), it eventually reset. it has now reset and seems to run much better but now i still cannot get any internet connection. it seems like it thinks my WiFi is set to "off" constantly, no matter what i try.

please advise if any of you guys would think what to do next? i have been on eBay and new WLAN cards are less than £5 so willing to try this, but im just so so frustrated as this has all happened since simply updating to Windows 10

thank you all in advance,

Jake