I can't access "other" folder on lumia 930 phone which shows as 20 gb full! Anyone got any ideas? I can't see it at all on a pc when connecting
A very common problem to most windows phones after large updates!
There are two ways to fix this: Easy one first - Just pack up all your stuff and send them to OneDrive. Not just using backup and restore section of your settings, but manually too. Then in settings hit 'reset phone' in about section. Plug in your phone while you do some other stuff. Finally after the gears are gone, you get your phone free of those 20GB of junk.
There's another risky way without resetting your phone. (but that's really very risky!) Comment if you want to know. Hope this answer helped you. If it did, give me an upvote!