Further Developments:

Today I went to a Vodaphone store to configure a replacement iPhone and ran into the same problem – my Hotmail froze and the appliance started to overheat.   This has now been occurring over 3 months and numerous devices.

One of the technical support staff mentioned that he had experienced the same problem with his Hotmail account due to Hotmail having moved some accounts to new servers.  This was resolved by his account being moved back to the old servers.  Could you please do the same for my account and let me know when it has been moved?

Many thanks,

Tim Davies