I recently deleted whatsapp from my Nokia lumia 520 because it wasn't notifying me when i got a message, i then tried to reinstall it and it wouldn't let me, whatsapp plays a vital part in my life as i have family and friends too far away to ring or text for free, how can this problem be sorted quickly?

your phone memory is full now you have to delete some app and then try to reinstall what up app again it must be solved your problem

Try removing the battery. wait a few seconds, reinstall and try to turn on. If that doesn't work, do a search for 'hard reset Lumina 520'.

Hello. To which network has your Nokia Lumia 520 been locked to.? You can get the unique unlock code for a Nokia Lumia 520 from Unlock-Zone.com at affordable cost. Good luck.

-<()>--<()>--<()>--<()>--<()>--<()>--<()>-
..............UNLOCKING INSTRUCTIONS..............
-<()>--<()>--<()>--<()>--<()>--<()>--<()>-

1 - Switch on your Nokia Lumia 520 without any sim card.
2 - Don't bother as to what is displayed on your Nokia Lumia 520.
3 - Compose #pw+CODE+1#.
4 - The Nokia Lumia 520 would then display the message "SIM Restriction Off" and will be unlocked!

Note :For Nokia Lumia 520 mobile phones locked to the network Fido or Rogers in Canada follow these instructions :
1 - Switch on your Nokia Lumia 520 without any sim card.
2 - Don't bother as to what is displayed on your Nokia Lumia 520.
3 - Compose #pw+CODE+7#.
4 - The Nokia Lumia 520 would then display the message "SIM Restriction Off" and will be unlocked!

The letter p appears if you press the button star(*) three times quickly
The letter w appears if you press the button star(*) four times quickly
The symbol + appears if you press the button star(*) two times quickly
The CODE you need to enter is the unique unlock code for your Nokia Lumia 520

SOURCE: MobileUnlockGuide.com

Parental controls must be set on the phone.

If you are the owner of the phone you should be able to clear it. Otherwise you will have to approach the owner of the phone to remove parental control and allow you to download the applications.

See set up of Kids corner for Windows phone.
People

Hi. You can get the accurate unlock code for your network locked Nokia Lumia 520 either from the respective network provider or from trusted online vendors like MobileUnlockSolutions.com at affordable cost.

-<()>--<()>--<()>--<()>--<()>--<()>--<()>-
..............UNLOCKING INSTRUCTIONS..............
-<()>--<()>--<()>--<()>--<()>--<()>--<()>-

1 - Switch on your Nokia Lumia 520 without any sim card.
2 - Don't bother as to what is displayed on your Nokia Lumia 520.
3 - Compose #pw+CODE+1#.
4 - The Nokia Lumia 520 would then display the message "SIM Restriction Off" and will be unlocked!

Note :For Nokia Lumia 520 mobile phones locked to the network Fido or Rogers in Canada follow these instructions :
1 - Switch on your Nokia Lumia 520 without any sim card.
2 - Don't bother as to what is displayed on your Nokia Lumia 520.
3 - Compose #pw+CODE+7#.
4 - The Nokia Lumia 520 would then display the message "SIM Restriction Off" and will be unlocked!

The letter p appears if you press the button star(*) three times quickly
The letter w appears if you press the button star(*) four times quickly
The symbol + appears if you press the button star(*) two times quickly
The CODE you need to enter is the unique unlock code for your Nokia Lumia 520

Just from the Google store or the Nokia store. The app will cost 89 ct every year.

Hi. You can unlock a Nokia Lumia 520 safer and easier using unlock code. You can get the accurate unlock code for your Nokia Lumia 520 either from your respective network provider or from any trusted vendor online like TheUnlockArena.com at affordable cost.

-<()>--<()>--<()>--<()>--<()>--<()>--<()>-
..............UNLOCKING INSTRUCTIONS..............
-<()>--<()>--<()>--<()>--<()>--<()>--<()>-

1 - Switch on your Nokia Lumia 520 without any sim card.
2 - Don't bother as to what is displayed on your Nokia Lumia 520.
3 - Compose #pw+CODE+1#.
4 - The Nokia Lumia 520 would then display the message "SIM Restriction Off" and will be unlocked!

Note :For Nokia Lumia 520 mobile phones locked to the network Fido or Rogers in Canada follow these instructions :
1 - Switch on your Nokia Lumia 520 without any sim card.
2 - Don't bother as to what is displayed on your Nokia Lumia 520.
3 - Compose #pw+CODE+7#.
4 - The Nokia Lumia 520 would then display the message "SIM Restriction Off" and will be unlocked!

The letter p appears if you press the button star(*) three times quickly
The letter w appears if you press the button star(*) four times quickly
The symbol + appears if you press the button star(*) two times quickly
The CODE you need to enter is the unique unlock code for your Nokia Lumia 520

go to your app store, look for the whatsapp app and download whatsapp for free

I have seen a feature in older phones that you can see files received via bluetooth in settings>bluetooth>received files