Do you seek about how to fix error 21 on an iPad? In some point while updating or restoring an iPad with iTunes then error 21 may emerge. Typically it is found that sometimes some hardware issue such as when faulty USB port or cable would responsible for the error. By the way you can fix error 21 on an iPad through iTunes Network Connectivity Tests. So you can try these feasible steps as follows:
- Start iTunes and "Run Diagnostics" needs to be selected from Help menu.
- Choose "Network Connectivity Tests," "Device Connectivity Tests" and then "Device Sync Tests" through checking at check boxes. "CD/DVD Drive Tests" needs to be cleared from check box.
- Now click at the "Next" button. Follow onscreen prompts then again click at "Next".
- Then choose at "Help" button which appears as items marked and onscreen instructions needs to be followed.
- Then restart computer as well as iPad. Update or restore iPad.
Hope these above mentioned measures would fix error 21 on an iPad, however at meanwhile in case of data loss happening scenario, iPad Recovery Software can be taken into consideration for restoring of lost, damaged or inaccessible from iPad. It is proficient solution for restoring lost iPad file.