When I try and delete a portal, I am getting the following error:

Error: Portals is currently unavailable.
DotNetNuke.Services.Exceptions.ModuleLoadException: Timeout expired. The timeout period elapsed prior to
completion of the operation or the server is not responding. ---> System.Data.SqlClient.SqlException: Timeout expired.
The timeout period elapsed prior to completion of the operation or the server is not responding. 
at System.Data.SqlClient.SqlConnection.OnError(SqlException exception, Boolean breakConnection) 
at System.Data.SqlClient.SqlInternalConnection.OnError(SqlException exception, Boolean breakConnection) 
at System.Data.SqlClient.TdsParser.ThrowExceptionAndWarning(TdsParserStateObject stateObj) 
at System.Data.SqlClient.TdsParser.Run(RunBehavior runBehavior, SqlCommand cmdHandler, SqlDataReader dataStream, 
BulkCopySimpleResultSet bulkCopyHandler, TdsParserStateObject stateObj) 
at System.Data.SqlClient.SqlCommand.FinishExecuteReader(SqlDataReader ds, RunBehavior runBehavior, 
String resetOptionsString) 
at System.Data.SqlClient.SqlCommand.RunExecuteReaderTds(CommandBehavior cmdBehavior, RunBehavior runBehavior, 
Boolean returnStream, Boolean async) 
at System.Data.SqlClient.SqlCommand.RunExecuteReader(CommandBehavior cmdBehavior, RunBehavior runBehavior, 
Boolean returnStream, String method, DbAsyncResult result) 
at System.Data.SqlClient.SqlCommand.InternalExecuteNonQuery(DbAsyncResult result, String methodName, 
Boolean sendToPipe) 
at System.Data.SqlClient.SqlCommand.ExecuteNonQuery() 
at Microsoft.ApplicationBlocks.Data.SqlHelper.ExecuteNonQuery(SqlConnection connection, CommandType commandType, 
String commandText, SqlParameter[] commandParameters) 
at Microsoft.ApplicationBlocks.Data.SqlHelper.ExecuteNonQuery(String connectionString, CommandType commandType, 
String commandText, SqlParameter[] commandParameters) 
at Microsoft.ApplicationBlocks.Data.SqlHelper.ExecuteNonQuery(String connectionString, String spName, 
Object[] parameterValues) 
at DotNetNuke.Data.SqlDataProvider.DeletePortalInfo(Int32 PortalId) 
at DotNetNuke.Entities.Portals.PortalController.DeletePortalInfo(Int32 PortalId) 
at DotNetNuke.Entities.Portals.PortalController.DeletePortal(PortalInfo portal, String serverPath) 
at DotNetNuke.Modules.Admin.Portals.Portals.grdPortals_DeleteCommand(Object source, DataGridCommandEventArgs e)
 --- End of inner exception stack trace ---

Every other portal operation (running SQL commands in the SQL window, User operations, etc.) run like they normally do. The SQL Server DBAs are reporting that they are not seeing activity when I try and delete a portal.

Anyone else seeing this and how did you get around it?

This started happening on a previous version of DNN (5.1) but it is continuing under the latest version.