Problem deleting

I have a sick subscriber in a transactional replication.
I want to delete it but I don't succeed.
When I try from Tools\Replication\Create and manage publications Entreprise Manager crush.
I try with
exec sp_dropsubscription @.publication = N'PublicationName', @.article = N'all', @.subscriber = N'SubscriberName', @.destination_db = N'DatabaseName' but execution take a long, long time ..without any end.
I don't want to delete all replication.
Any ideeas?
10x a lot!Whats the size of Subscriber?
Check for any other errors from SQL error log.|||In the end I deleted all replication and recreated it. Now it's working.