These are the steps I used to resolve the issue, you may want to check with support prior to going ahead but this is what worked for me.
Following some discussions with the support team, we found that the solution is to firstly quarantine the Virus then Delete it.
Then delete the following 'Configuration Folders'
C:/Users/USER_NAME/AppData/Roaming/Adobe/Extension Manager CS5/en_US/Configuration
Restart your system and Run a Full Deep Scan. The Virus should not be present.
Re Open Dreamweaver and check for errors, everything should be ok, Extension Manager may want to update Dreamweaver with the HTML5 pack,
Then Reinstall the extensions one at a time OLDEST first, activate each one and restart Dreamweaver after each installation to ensure everything is ok.
I hope this helps, sorry for the delay as you can imagine, it took a while to sort out.