Don't know if this is the correct forum but I suddenly have a new problem this am. I cannot access any websites with 'secure access' facility (such as banks, Amazon etc). Either via Firefox or IE. Other (non secure) sites have no problem. I have not added/deleted anything recently.
Any ideas?

Try this:

Click Start.
Click Run.
Type regsvr32 softpub.dll
Click OK. A pop-up should display with the message Dll Register Server in softpub.dll Succeeded.
Click OK

Did not have any effect.
The message I get is:

"the connection was refused when attempting to contact............".

It only happens to secure sites though. All very strange, especially as it just started this am.
Anything else I can try? I'm desperate to do some on-line banking.

Dis-able your Norton Tools etc to see if the problem is being caused by a config setting in that.

Negative, I'm afraid. I deleted the Norton stuff (via start/run/configure/startup) but it made no difference. I can get into this site, for example, it's only the secure ones that are the issue. What controls this? There must be something suddenly stopping the access.

proxy servers also affect this, if u use one make sure it's correct, if u don't and there is one in there then remove it! You'll find it under tools, internet opstiong, connections, LAN Settings

do u use dial up or broadband for your connection??? might need to talk to ur isp, maybe they've put a proxy server in for secure access or something...