Microsoft suggest this may be the cure:
To resolve this problem, follow these steps:
Restart your computer in Safe Mode.
Click Start, point to Settings, and then click Control Panel.
In the System Properties dialog box, click the Device Manager tab.
Click View devices by connection.
In the device list, click AOL Adapter, and then click Remove.
When the confirmation message appears, click OK.
Repeat step 6 for each of the following devices:
AOL Dial-Up Adapter.
Dial-Up Adapter #2 (VPN Support).
Restart your computer in Normal mode and install AOL.
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