iPhone 3GS Software Update Issues

I recently upgraded the software on an iPhone 3GS to the newer firmware / software version 4.1 from version 3. The upgrade was not as smooth as I was hoping, as I ran into a few issues along the way.

The process I went through, was to first update iTunes to the latest version. After iTunes was updated I connected the iPhone, which iTunes detected as expected. I was then prompted to update the software on the phone to the latest version, which I accepted. The update was downloaded, but while applying to the phone, I started receiving error messages in iTunes during the sync (device error, device not found). A final message was displayed saying that the operation had failed, and when i returned to the iPhone, I found that it was no longer functional. The phone displayed the screen requesting that I connect it to iTunes.

I turned the iPhone off and then back on again, which did not help at all. Connecting the iPhone back into iTunes resulted in a series of the same error messages displaying. iTunes detected that there was an error, and gave me only one option to "Upgrade, and restore from backup". After accepting, I watched and waited as the phone went through the upgrade process again from scratch. This time, the upgrade process completed successfully. It then restored from the most recent available backup, which was also applied successfully. I disconnecting the iPhone from the computer after the upgrade and restore to find that the firmware / software had been successfully updated, and that all existing data (contacts, messages, photos, apps, etc.) were still there.

There would be a number of possible causes of issues such as this, but in this case I am leaning toward the initial upgrade being interrupted prematurely, which left the phone in a semi-upgraded (non-functional) state. At the time, I was connected to the Internet using the Mobile (Wireless) Broadband connection, which has not been 100% stable in the past. The Internet was working both before and after the unsuccessful upgrade, but i suspect the the connection (mobile coverage) dropped out for a few brief moments during a critical stage in the process, which has in the past has caused issues. The computer used in this case is a 2 month old G7, which I have not experienced any issues with apart from this one so I don't think this was the cause.

If anyone has had similar issues, different opinions on the cause, or have resolved this issue using an alternative process, it would be good if someone can shed some light on the situation.

Related:
iPhone 3GS Camera Not Working

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