iTunes cannot backup because backup is corrupt

The clarification of the instruction is what assisted me the most. I was able to find the /lib and delete the old backups on my MAC and now backup is progressing without error!

Thanks to you Kelly 3 year later :-)

Kindest regards

Robert

Can I still back up my phone after I delete it? I gave my other phone to apple for a new one and when I tried to restore my new with my old phone back up it said it was corrupted would I still be able to get everything back?

This is a huge problem! I lost ALL of my data on my iPhone because a 'Senior Advisor' instructed me to delete all date from my iPhone and restore from back up only to discover EVERY backup I had as of recent was corrupt! What a nightmare!!! I had to restore my iPhone from anew which was a huge time hassle as well as loosing all recent photos and videos (that were important). Where the advisor went wrong, and where my intuition was right and I am kicking myself for not listening to my own gut instinct, was to not guide me to make another backup of my phones data BEFORE wiping the phone and trying to restore from backup. I am not a fan of iCloud, but for such an instance backing things up like my most recent photos and such in the cloud (or even on my Mac) BEFORE doing the restore would have been the way to go. The fact that they did not eve suggest it and missed this whole no apparent awareness of corrupt backup's is a gigantic thumbs down for Apple. Customer relations has heard from me loud and clear on this one!

The same problem happened with me. I deleted the backup and the error message still pops up. I don't know what to do.

did you ever end up fixing the problem? it's happening with me even after i deleted the backup. the error msg keeps appearing

I'm getting the same error on my iPad, there is no backup, I had deleted it before hoping that would resolve my issue but it has not. I have uninstalled reinstalled everything and it still does not work. I HATE itunes, the worst software that apple has released.

Someone please help so that I can backup up, and update my iPad.

I'm getting the exact same error message on the iphone 4 "backup is corrupt............", when I go to delete the backup there is no backup there! Does anyone know how to fix this without having to restore?

Also if I try sync apps I get the messgae "all existing apps and their data will be deleted".

Me, too. All backup files have been deleted from iTunes>preference>device (iphone & ipad). However, my 3GS will not back-up. Message is same as above. The phone will still sync. It just won't back-up.

i think i found a fix. from what I saw I had deleted the backup from preferences however the file was still on my machine. you have to find the actual file and delete it. for windows i wound it at

C:\Users\<user>\AppData\Roaming\Apple Computer\MobileSync

Thanks for the advice, I cannot seem to find the mobile sync file on Windows Vista though. what type of file it the mobile sync you deleted?

thank you! i had to make sure i closed iTunes first before deleting the files. had to go into one of the folders and delete most of the entries (i guess the folder was still in use somehow) but i can finally backup, sync, and download updates.

apple should include an option to wipe exisiting backups. this only happened after I started to sync more than one device to my machine.