I've read the FAQs for this and have tried to view/ adjust the proxy settings as you suggest. But I can't seem to get the tool to work though I'll admit I'm not entirely certain I know what I'm supposed to be doing. Strangely the tool was working fine until yesterday and AFAIK I haven't made any changes to any settings. Can you help?

Edit to say: As a last resort I decided to reboot my computer and that seemed to do the trick! I'm even more confused as to what caused the problem but at least now it seems to be back to normal.