email router rollups

I'm able to apply all rollups to and including 10 on all components of CRM 2011, except for mail router. I can work through to RU 6 no problems, but 7,8, and 10 all return an error that kb 2600460 isn't insalled.

I've gone back and applied rollup 3 , 4 , 5 and 6 all fine but not able to get any further.

Anyone else able to give some advice.

Thanks

Jock