Execute permission denied on object 'sp_addextendedproc', database 'master', owner 'dbo'
Problem: Can not log into the SQL database.
Possible Solution: The hard drive might be full. If you are using MS enterprise manager you can specify to truncate the transaction log. Another option is to set the transaction log recovery model to "simple". This eliminates the problem of huge transaction logs.
Note: However you will not be able to roll back the database to some point in the past
If you are doing all of the above you may have to look to see if some other item may be filling up the hard drive.