Q: i forgot my backup password.. how can i restore or give new password?

Howdy iamsree,

It sounds like you have an encrypted backup and do not remember the password. Take a look at these options for just such a situation from the following article:

About encrypted backups in iTunes

If you don't have your password:

• If someone else set up your device, check with them for the password. 
• Try using an iCloud backup instead. If you don't have an iCloud backup, you can make one.
• If it's still relevant, try using an older iTunes backup.

If you forgot your password, the only way to turn off backup encryption on your device is to erase your device and set up as new. Erasing removes all data from your device. If you don't want to erase your device, restore from an iCloud backup instead.

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