I had not exact but similar issue which may help you here. But I took a different (more risky) way to solve by editing registry values. Before you work with registry, make registry backup with ERUNT and take a fresh snapshot of the System Setting (i.e. Create
new System restore Point).
Go to Registry and Right-Click to save this hives: Network and TCPIP. (you can delete the DHCP address if you wish for theprivacy reasons.
[HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Network]
and
[HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\Tcpip]
Please post the content of these two hives, alongwith your Firewall and AV/AS software name. There is a possibility that you have a problem\corruption with network configuration. My take is that your Network adapter setting is corrupted by the AV/AS while
cleaning spyware/trojan.
Or, you can simply try resetting the network in the SAFE MODE:
RUN > netsh winsock reset
http://support.microsoft.com/kb/299357/en-us
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I would recommend to use RegAlyzer program to find all hidden registries with these key words: Symantec, Norton, NAV, SAV. You will be surprised that so many keys are still not cleared.
Additionally, Symantec stores files in (i) Windows\System32\drivers (ii) Windows\System32 (iii) Program Files\Common Files.
These locations also need to be purged of Symantec residues. One way to achieve this is to run through Windows PE Loader, and use RegistryEditorPE like program.