From
HERE
To contact a Microsoft customer service representative and activate Windows by phone:
1. Click Start, point to All Programs, point to Accessories, point to System Tools, and then
click Activate Windows.
-or- Click the Windows Activation icon in the status area of the taskbar.
2. Click Yes, I want to telephone a customer service representative to active Windows now.
3. Click Read the Windows Product Activation Privacy Statement, click Back, and then click Next.
4. Follow the steps that are displayed in the Activate Windows by phone dialog box, and then
click next. Please note: the number will be displayed at this point and will differ based on the
location you select.
5. When activation is complete and you receive the following message, click OK.