I've been waiting for the 10 update for my 640 xl for sometime, so I decided to take it upon myself to find out how to update it without waiting any longer. Turns out, windows insider is an app that allows windows phones without the 10 update to access it, although with a touch of danger to it, as if something goes wrong with the build, it can't fall back on 8.1 (or at least to my understanding). i went ahead with the update after backing everything up, and everything seemed to run well at first, except I couldn't download any MMS messages (Pictures, contacts, etc). Turns out my data wasnt working properly, so no internet or anything without Wifi, and after troubleshooting with at&t (my provider) for awhile, I went out to buy a new SIM card. After putting the new card in, I did a soft reset (up vol + power). When the phone turned back on, i had LTE! hallelujah! Only thing is now, i still cant download MMS, even though I have LTE.
Ive really enjoyed the 10 update thus far, and i can still use things like explorer and GPS with what i have, but not getting those messages will be annoying, any tips on what i could do without having to hard reset of reverting back to 8.1?