The people trying to upgrade their iPhones with the Apple’s recently released latest version of the iPhone operating system – iPhone OS 3.0 are having rather frustrating time.

There’s deluge of reports on internet and Twitter that the iPhone users trying to upgrade their iPhones with iPhone OS 3.0 are having problems.

According to reports, the people attempting to upgrade their iPhones with iPhone OS 3.0 are getting an error message, saying ““iPhone activation server is unavailable””.   

Furthermore, people are having problems in calling, sending picture messages and downloading. While downloading or installing the new software, people are getting error messages reading “iPhone activation server is temporarily unavailable”.

The problems are said to be surfaced due the overloading of Apple's servers. When reached out to Apple, the company declined to comment on the issue.