Updating to 2.0 with multiple iphones?

[frogpajamas]

I updated iTunes, and successfully updated my iPhone software. Now I'm trying to do the same with another iPhone that also syncs music/video with the same iTunes. The second iPhone usually has a name like "Johnny's iPhone" but now it just says "iPhone" and when I try to update it, it says

"An error occurred while backing up this iPhone (-35)
Would you like to continue using this iPhone without the backup?"

So I always cancel it. Can you only update one iPhone per computer?

 

[trollqueen]

same problem

I also am having the same error message. The difference is that I have only 1 iPhone attached and that was unable to install the update. I have iTunes 8 installed and still cannot install iPhone 2.0 without the error message.

I have read other lists and people have lost their data from their phones after continuing with the installation, even though they received an error message. As this is my only phone, I cannot risk the loss.