Any idea of this replication error?

Hi, all..
One database called POS in a server A is replicated with another server B with merge replication.

Server A is distributor and publisher.
I tried to replicate POS db it keeps giving me error following.

"SQL Server Enterprise Manager could not retrieve information about database 'POS'
Error 21776: [SQL-DMO] The name 'POS was not found in the ReplicationDatabase collection. If the name is a qualified name.
user [] to separate various parts of the name, and try again."

When other try it gives following error..
SQL Server Enterprise Manager could not enable database 'POS' for merge replication.
Error 20736: [SQL-DMO] This object has been dropped from the server.

I did all I can do..
I reinstalled sql server and tried again.. but it gives same error..

Does anyone has any idea of this problem??

Please post any idea.

Thank you...You are already doing merge replication with a database, and the server is giving you this error message when you try to do something to manage the replication (adding or deleting publications, etc) ?!?!

-PatP|||Thank you for reply.
I got same message after reinstalling with folder 'microsoft sql server' clean up when I tried to replicate the DB!!!

I think some other place eg) window register.. or what..(sounds strange..)
keep the information and blocking..|||Is it possible POS merge replication information is saved on the other computer? Therefore it gives SQL-DMO error?
Any comment helps..