Microsoft® offers automatic fix for Windows® 7 upgrade issues
An automatic fix has been made available by Microsoft to resolve failed upgrades from Windows Vista to Windows 7 when the process hangs indefinitely at 62% level.
With the formal launch of Windows 7 on October 22, 2009, eligible users running Windows Vista start migrating to Windows 7. While migrating, several users found that the transition from Windows Vista to Windows 7 is not easy as sometimes it stops responding at 62% which creates a problem for the users. In such cases, the operating system also creates a file labeled system_drive:\$WINDOWS.~BT\Sources\Panther\setupact.log. The specific log entries contained by this file are cited in KB975253.
Microsoft explained that the cause of this problem is the Iphlpsvc service which stops responding during the upgrade. Other services can also be the cause of a problem when process stops responding at 62%. Though Microsoft does not have an update to fix this issue but there is a solution to it, which can be manually deployed. But at the same time, it also has made an automatic fix that can be seamlessly deployed by Windows 7 customers affected by this issue.
Microsoft explained that to fix this issue automatically, restart the computer where upgrade stops at 62%. Your computer would come back to Windows Vista. Now either download the (Automatic fix) to a flash drive or to a CD or on the machine where upgrade failed. Click the "Fix this problem link," where you have encountered this problem. Click Run in the File Download dialog box, and follow the steps in the Fix it wizard.
To fix this problem yourself, try the following steps:
STEP 1. Restart the computer. Then, your computer will roll back to Windows Vista.
STEP 2. Click Start, right-click Computer, and then click Properties.
STEP 3. On the Advanced tab, click Environment Variables.
STEP 4. Under System variables, click New.
STEP 5. Type MIG_UPGRADE_IGNORE_PLUGINS in the Variable name field.
STEP 6. Type IphlpsvcMigPlugin.dll in the Variable value field.
STEP 7. Click OK three times to close the dialog boxes.
STEP 8. Start the upgrade installation again.
After the workaround has been accomplished, either automatically or manually, users should no longer face any issues when migrating from Windows Vista to Windows 7.