Cannot show requested dialog (SqlMgmt).
Applies to: Microsoft SQL Server 2005.
Error Message.
Microsoft SQL Server Management Studio (SSMS) showed the following error when
trying to access the Properties of a given database:
Cannot show requested dialog (SqlMgmt)
An exception occurred while executing
a Transact-SQL statement or batch.
(Microsoft.SqlServer.ConnectionInfo)
Lock request time out period
exceeded. (Microsoft SQL Server, Error: 1222)
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Cause.
An index defragmentation process was running on some of the database tables
when SSMS threw the error.
Solution.
After the defragmentation process finished, SMSS was functioning as usual.