We have recently been alerted by a number of our customers that their iPhones have been 'dying' following upgrading them to Apple's new handset operating system.

iPhone 3GS owners have been prompted to upgrade to the new phone software – iOS4 – by iTunes. However, in many cases the upgrade fails to install properly, leaving users completely unable to operate their touch screen phones.

The way this occurs is that iTunes pops up a message to offer you an upgrade, so of course you say yes.  When you next connect your iPhone to iTunes, you are prompted to upgrade the new all singing and all dancing iOS4 operating system.

After the iPhone upgrade downloads from the internet you might be lucky and everything works like a dream, but we’ve seen lots of cases of the upgrade installation failing.

This isn’t a small problem; the iPhone will go completely dead, showing either a ‘loading bar’, Apple logo or restore graphic on the screen, and iTunes will display an error code – likely to be ‘error 21’.

We’ve developed a workaround which we are confident will work in the majority of cases – provided of course nothing else is wrong with users’ phones.

The 'fix' for iPhone 3GS users is posted on The PC Support Group website (http://pcsupportgroup.com/iphone-os4-fix.phuse).