error 633

Error 633 is a Windows error that occurs when attempting to establish a dial-up connection through a modem after resuming a computer from sleep or hibernation. This issue has been documented in Windows 7 and Windows Server 2008 R2. The error typically prevents the modem from being used for dial-up networking until the system is restarted. Microsoft has released a fix for this problem, which is available through a knowledge base article. Users experiencing error 633 should apply the relevant update to resolve the connectivity issue. The error is specific to dial-up modem connections and does not affect broadband or wireless connections.