Ok, this looks like it's an issue with the latest Microsoft security update, which landed on Tuesday.

It looks as if some Active X controls have been disabled, this appears to have an effect on Lightstreamer, although I don't know what or why exactly.

We found a workaround by adding our webserver as a trusted site in IE6. Then we reset the custom settings for the trusted sites zone to 'Low' and enabled the option "Initialize and script ActiveX controls not marked as safe". The lightstreamer app is now working as it should.

I don't know quite how we're going to cope with this going forward, it may be that we recommend that the clients use Firefox or IE7, where this problem doesn't exist. For the meantime at least we have this somewhat awkward workaround

Cheers,

Richard