Registration / Login Issues
First of all, you need to make sure you are entering your cell phone number in the international format:
+(country code)(city or carrier code)(your number)
Let's say you live in the U.S.A. and your cell phone number is 555-123-4567, then you need to enter
As of 7 February 2017, Telegram now supports VoIP numbers, so you can now register with virtual numbers such as numbers issued by Google Voice.
If you have a real SIM card phone number and it's not a virtual number (VoIP), contact email@example.com and provide the following details to them:
- Which company did you get your SIM card from?
- What country are you in right now?
- Are you able to receive SMS? Try sending and receiving messages from friends. If not, you are not able to log in to Telegram.
Country specific SMS delivery issues
Brazil: Oi, formerly known as Telemar, is the largest telecommunications company in Brazil and South America. They offer their customers a website where they can configure their account, e.g. blocking SMS from short numbers. It's important to disable the setting, in case you do not get any verification/login SMS. Login to http://minha.oi.com.br and disable Recepção de Sons Imagens e Bate papo.