Apex data loader failed to send request
Here is an easy way to find out. Download Demand Tools, they have a 5 day trial and see if the connection works.
if it does then perhaps a re-install of the Data Loader is in order. If Demand tools also experiences a connection issue then you might re-test from another location
It was a proxy settings issue which has since been resolved. Thanks for your help.
Is anyone have solved it?