This isn't really a Plusnet issue, except that it would affect your ability to use the BT ADSL speedtester. So, just in case anyone else has had the same problem, this might save you some time.
Following the latest Java update (v6 update 18), Java would start then close with a 'java.exe has encountered an unexpected problem' alert. This was on a PC running a fully-patched version of Windows XP. The problem affected both Firefox 3.5.7 and IE 8, so I don't think it's browser-related. To cut a very long story short, I eventually found that there was a Java setting that fixed the problem if I unticked the relevant box.
If you have the same problem, open the Java control panel (Start menu.. Settings.. Control Panel.. Java), then choose the 'Advanced' tab. Click on the plus sign to expand the 'Java Plug-in' branch and untick the box marked "Enable the next-generation Java Plug-in (requires browser restart". Click 'Apply' then 'OK', close down the Java control panel, restart your browser and Java should work.
Most people won't have this problem - I haven't seen anything else about it, so it may just be a peculiarity of my setup. But if you do have the problem it can take a while to find out what's wrong.
Graham
