Can an unlocked iphone upgrade to ios 7 beta?

[daniel]

Hi i have been trying to update my friends phone to ios seven beta but i keep running to the unconpatible firmware i have tried downloading the firmware for both model

Cdma and gsm but no dice i also tried downloading it from multiple sites but no luck can you tell me what im doing wrong what i should do and or if an unlocked phone can be upgraded btw i tried both holding shift an clicking update and holding shift and clicking restore ps its my friends phone so i dont know if its been factory unlocked or hack unlocked

[returned]

I think when you restored the unlock also was revoked. If it had been a permanent unlock then you would not have faced this problem. I suggest you can approach Superunlockcodes.com and specify the country,locked network of iPhone .Based on the availability you can get the permanent unlock service along with free instructions. Once unlocked you can upgrade to latest iOS by visiting the apple website.