This issue occurs because the Iphlpsvc service stops responding during the upgrade. It’s also important to note that other services may also cause a problem in which the upgrade process stops responding at 62%.
To fix this issue manually, do the following;
7. Click OK three times to close the dialog boxes.
8. Start the upgrade installation again.
Alternatively, to fix this problem automatically, restart the computer where the upgrade to Windows 7 fails at 62%. Your computer will roll back to Windows Vista. Browse to Microsoft KB975253, then click the Fix this problem link.
Note: If you are not on the computer that has the problem, you can save the automatic Microsoft Fix it 50319 to a flash drive or to a CD, and then you can run it on the computer that has the problem.