Files keep deleting ever since Windows 10 upgrade.NO windows store and windows widgets?

[WPCentral Question]

I upgraded my computer to Windows 10 recently.But after that,whenever I log in,files keep getting deleted.One day,I saved my assignments onto the computer.The next day,BAM it's gone,followed by other apps like spotify etc.It's really frustrating as I have to keep redownloading everything,only to find that it's deleted the next day.On that of that,I don't have a windows store and windows widgets like timer etc.I desperately need help as it's been going on for the past few days and I have tons of assignments to submit soon.