The Yamaha AN1x Synthesizer mailing list

I'm using Outlook under Windows XP and it's behaving normally and putting 
messages from this group (and others) where the rules tell it to.

I'm in the UK using Virgin as my ISP.

However, I've had some other bizarre behaviour since I moved to XP and in 
general I've learned to regard periodic failures like this as normal for 
Microsoft products.  (I've got a totally outlandish problem with Media 
Player right now).  And I think what you're describing has happened to me 
with previous versions of Windows.

I'd suggest deleting the rule and re-creating it.

But yes, Yahoo groups do odd things as well, so I'm not surprised you 
suspected something on the Yahoo side of things.