I tried http://localhost:4750/qvws.asmx and i've the same response, but i think i'ts correct because you're calling the "QlikView Web Server" webservice interface, not the QlikView Web Server. I don't think it have to reply something.
Chekc if you have some plugin in your browser for the 1/10 seconds refresh.
hmm I could have swore I thought the QV webservices all return some sort of "Hello World!" and alternate address for WSDL, but I guess I'm wrong.
In any event...Here is some further information.
The first time the access point was hit (out of box QV access point) the user clicked Log Out, then tried to log back in, at that point it started continuously refreshing the browser.
No additional plugins have been installed.
Correction: It is WIndows 2008 standard edition with 4GB ram.