In UK have Lumia 635 on proper 8.1...i also have insider app to allow wp10 preview,...signed into it...but it says no builds?any ideas people why I can't get preview wp10?????...please.
Are you registerd as a insider? you must have at least 8.10.14219.341 or lower on your phone. Plus have enough memory free. Read the notes on MS site (click on ''your phone meets the system requirements'' if that didn't help
If you have a micro sd card then put the moveable apps onto it to clear up more space on your phone then try again as you should have 3gb or more I'd recommend before using win10 tp.