Problem is with the charger you're using. May be it's from manufactures other than your device's. It'll have different amperage and will affect your phone. You might not face any problems with charging via PC or laptop as it's current is lower as compared to normal wall chargers. Only I can say is, get a new generic charger asap.
Windows Phone 7.x only allows apps to be installed via the store app itself; Whilst you can download the xap from the store, you can only use this to install on phones running Windows Phone 8.0 or later.
Do the following:
2.Get external charger 2amp recommended.
3.Charge it with external charger.
4.Charge for an hour and insert back battery.
5.Check if your phones question mark gone and it can open.
6.If it is opened then try to charge with normal charger.
:) Tell me if this didn worked.
I had a similar problem with my old HTC 8s. First i thought it's a hardware issue, but after cleaning micro usb port with ear buds and replacing my usb cable the phone started to charge properly. Some devices are sensitive to dust etc. so it's good to clean those ports from time to time.
If the file opened an app when you transferred, you need to see if the app saved it. Since you mentioned it was a PDF, both Microsoft and adobe PDF apps save the files to their isolated storage. You can go into the app and select the file or files you want and delete them.
No, developer unlocking a phone does not provide you with similar "rooting" abilities as other phones. If your carrier has locked the option to tether. So, unless you pay, your only option is to switch carriers.
I purchased a pad called Samsung easy charge at Best Buy. It was for some Galaxies, not all, but it charges my Nokia Lumia 920 beautifully. I tried it at the store before buying. Best Buy does not deal with Windows phones so they don't sell the pads for Nokia, but this worked for me. My grandson has a Samsung Galaxy, and the charger did not work for his ...