Dial-Up Modem or PPPoE is Unavailable

Resolution :

Start >> Run >> Regedit
HKEY_LOCAL_MACHINE >> SYSTEM >> CurrentControlSet >> Services >> RasMan >> PPP >> EAP
Delete the sub-keys listed except 4 & 13

Start >> Run >> services.msc
Set these three to "Automatic": Remote Access Connection Manager, Remote Access Auto Connection Manager and Telephony.