#6 Corresponding publication 'pub1' not found on server side

[Neeraj khanna]

I m using the SQL Server as the publisher and the
subscriber.I published a table with the name pub1 on the
port 3001. The i m subscribing it on the port 3002 with
the name sub1.Then i m also publishing a table with the
name pub1 on 3002 port on any table.Then i m trying to
make a subscription with the name sub1 using pub1 of
the port 3002.Then it gives the message :
Subscription 'sub1' is already subscribed. to
Publication 'pub1'.
After clicking the ok i droping the publication pub1 of
3002.But when i tried to drop the subscription sub1 of
the 3002 then it is giving me the following message:
Corresponding publication 'pub1' not found on server
side.Altough the pub1 on 3001 it is existing.
After that if i m taking the snapshot or performing the
syncronization it

gives the message :

Problem in getting snapShot for Subscription 'sub1'
due to -- 'null'.
But when i restarted the both replicators the it easily
drop the subscription and then publication.