Apple customers are not happy after having problems upgrading to the new version of the iPhone’s mobile operating system, iOS 5, on Wednesday.

Taking to Twitter, Facebook and Apple’s support forums, users reported that their phones and tablets had been wiped — or worse, bricked. So many people were having problems with the update that the upgrading error message, “error 3200,” nabbed a spot as a worldwide trending topic on Twitter.

On Apple’s forums, several users reported similar stories to this one, from a user with the handle kxmx43: “Plugged into iTunes (fully updated) and downloaded iOS 5. Began installing and errored out. Lost everything. iPhone now stuck in Recovery Mode and won’t update to iOS 5.”

According to posts on the support forums, the company told users that 3200 errors meant that there was simply too much network traffic to process requests and that users should try again later. Others found that downloading the update straight from Apple’s Web site instead of upgrading from within iTunes worked more quickly, but that wasn’t the case for all users, Gizmodo reported.

For those whose phones were wiped or frozen, many found that resetting the device and restoring it from the back-up files on their computers took care of most of the problems.

Users also reported problems registering with Apple’s iCloud service and enabling cloud backups as upgraders rushed to make new accounts.

InformationWeek pointed out that Wednesday’s upgrade woes had echoes of Apple’s joint iPhone 3G/iOS 2 launch in 2008. With the iPhone 4S launching Friday, Apple should make sure that its servers can take another hit from phone activations.

If you haven’t upgraded yet, do yourself a favor and back up your iDevice before you take the plunge. You can do this manually by control-clicking or right-clicking your iPhone, iPod or iPad in iTunes and selecting “Back Up.” In the event you run into some problems, you can get back your information by choosing ”Restore from Backup” in the same menu.

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