>> "e" == e fraga <e.fraga@ucl.ac.uk> writes:

   > On Wednesday, 21 Jan 2015 at 15:07, Uwe Brauer wrote:
   > [...]

   >> It seems that some index needs to be actualised but how? 
   >> I tried gnus-expunge-group, without success.
   >> 
   >> Any help is appreciated.

   > I have found that typing M-g on the group line in the group buffer
   > sometimes helps.

Thanks! I killed the group and then re-subscribed and that helped as
well.