When you can't get to your data because another application has it locked, a thorough knowledge of SQL Server concurrency will give you the confidence to decide what to do.
Download your free copy of SQL Server Concurrency: Locking, Blocking and Row Versioning, the new eBook by world-renowned SQL Server trainer Kalen Delaney, dive into SQL Server's models for concurrent access, and learn how to troubleshoot blocking, deadlocking, and update conflicts.
The simplest way to catch these problems on your servers is with SQL Monitor, so grab a free trial and see how quickly you can put Kalen's tips into practice.