I personally think it's a bug on Window 7 since the upgrade button and product key field are disabled and hidden. However, it's possible to bring it back by using Anvir Task Manager. So here is an instruction:
1. Download and install Anvir Task Manager trial version.
2. Start -> Control Panel -> Programs and Features
3. Select Microsoft Visual Studio 2008 Professional ENU, click Uninstall/Change.
4. click "Next >>".
5. You should see "Add or Remove Features", "Repair/Reinstall", "Uninstall Microsoft Visual Studio 2008" on the next screen. DO NOT click ANY of them. The controls you want are hidden just under these three options.
6. Launch AnVir Task Manager as an Administrator.
7. In the Applications tab, find Microsoft Visual Studio 2008 Setup - Maintenance Page. Right-click this item and select "Detalied Info".
8. In the bottom panel, click "Windows".
9. In the bottom panel, expand "Microsoft Visual Studio 2008 Setup, the Maintenance Page".
10. As you can see, several items have no name. Go to the bottom, you see "Visual Studio Setup Banner". Expand the anonymous item just above "Visual Studio Setup Banner".
11. In the newly expanded item, you will see a number of grayed-out lines and icons. This indicates they are hidden. For each disabled line, right-click and select "Visible", then right-click and select "Enabled". Don't forget to include the item in this list labeled "Upgrade" - that is the button to submit the license key data.
12. Check your Visual Studio maintenance window. You should see the controls to enter your license key there. Put in the license key and click "Upgrade".
1. Download and install Anvir Task Manager trial version.
2. Start -> Control Panel -> Programs and Features
3. Select Microsoft Visual Studio 2008 Professional ENU, click Uninstall/Change.
4. click "Next >>".
5. You should see "Add or Remove Features", "Repair/Reinstall", "Uninstall Microsoft Visual Studio 2008" on the next screen. DO NOT click ANY of them. The controls you want are hidden just under these three options.
6. Launch AnVir Task Manager as an Administrator.
7. In the Applications tab, find Microsoft Visual Studio 2008 Setup - Maintenance Page. Right-click this item and select "Detalied Info".
8. In the bottom panel, click "Windows".
9. In the bottom panel, expand "Microsoft Visual Studio 2008 Setup, the Maintenance Page".
10. As you can see, several items have no name. Go to the bottom, you see "Visual Studio Setup Banner". Expand the anonymous item just above "Visual Studio Setup Banner".
11. In the newly expanded item, you will see a number of grayed-out lines and icons. This indicates they are hidden. For each disabled line, right-click and select "Visible", then right-click and select "Enabled". Don't forget to include the item in this list labeled "Upgrade" - that is the button to submit the license key data.
12. Check your Visual Studio maintenance window. You should see the controls to enter your license key there. Put in the license key and click "Upgrade".
