Error: For security reasons DTD is prohibited in this XML document

I was having trouble this evening running some of the Office Dev PnP samples from home.  I was consistently getting the following error when trying to connect to my Office 365 developer tenant.

“For security reasons DTD is prohibited in this XML document. To enable DTD processing set the DtdProcessing property on XmlReaderSettings to Parse and pass the settings into XmlReader.Create method.”

After assuming that I was entering in the username and password information incorrectly, I decided to try and see if there was some information out there on this error and I came across the following article (http://pryankrohilla.blogspot.co.uk/2014/05/error-resolved-connect-sposervice-for.html), which indicated this was an issue with my ISP (Virgin Media), after changing my DNS settings  to use Googles DNS Servers (8.8.8.8, 8.8.4.4) the sample code started working.

God knows why Virgin have decided to do this, but thanks for wasting my time this evening.