Exception when creating dummy server

When I try to create a dummy server (with any name), I get the error below. BuildMaster does succeed in creating the dummy server, but it has no name. I then can edit the details of the no-name dummy server and give it a name, and it takes the name just fine.

Server Error in '/' Application.

2627141Environments_CreateOrUpdateServer22`Violation of UNIQUE KEY constraint 'UQ__Servers__Server_Name'. Cannot insert duplicate key in object 'dbo.Servers'.

Description: An unhandled exception occurred during the execution of the current web request. Please review the stack trace for more information about the error and where it originated in the code.

Exception Details: System.Data.SqlClient.SqlException: 2627141Environments_CreateOrUpdateServer22`Violation of UNIQUE KEY constraint 'UQ__Servers__Server_Name'. Cannot insert duplicate key in object 'dbo.Servers'.

Source Error:

An unhandled exception was generated during the execution of the current web request. Information regarding the origin and location of the exception can be identified using the exception stack trace below.

Stack Trace:

[SqlException (0x80131904): 2627141Environments_CreateOrUpdateServer22Violation of UNIQUE KEY constraint 'UQ__Servers__Server_Name'. Cannot insert duplicate key in object 'dbo.Servers'.] System.Data.SqlClient.SqlConnection.OnError(SqlException exception, Boolean breakConnection, Action1 wrapCloseInAction) +388
System.Data.SqlClient.TdsParser.ThrowExceptionAndWarning(TdsParserStateObject stateObj, Boolean callerHasConnectionLock, Boolean asyncClose) +688
System.Data.SqlClient.TdsParser.TryRun(RunBehavior runBehavior, SqlCommand cmdHandler, SqlDataReader dataStream, BulkCopySimpleResultSet bulkCopyHandler, TdsParserStateObject stateObj, Boolean& dataReady) +4403
System.Data.SqlClient.SqlCommand.FinishExecuteReader(SqlDataReader ds, RunBehavior runBehavior, String resetOptionsString) +6665769
System.Data.SqlClient.SqlCommand.RunExecuteReaderTds(CommandBehavior cmdBehavior, RunBehavior runBehavior, Boolean returnStream, Boolean async, Int32 timeout, Task& task, Boolean asyncWrite) +6667768
System.Data.SqlClient.SqlCommand.RunExecuteReader(CommandBehavior cmdBehavior, RunBehavior runBehavior, Boolean returnStream, String method, TaskCompletionSource1 completion, Int32 timeout, Task& task, Boolean asyncWrite) +577 System.Data.SqlClient.SqlCommand.InternalExecuteNonQuery(TaskCompletionSource1 completion, String methodName, Boolean sendToPipe, Int32 timeout, Boolean asyncWrite) +735
System.Data.SqlClient.SqlCommand.ExecuteNonQuery() +290
Inedo.Data.DatabaseFactory.Inedo.Data.IDatabaseExecuter.ExecuteNonQuery(String storedProcName, DbParameter[] parameters) +268
Inedo.BuildMaster.Web.Controls.Extensions.AgentEditorHost.SaveExtension() +300
Inedo.BuildMaster.Web.Controls.Extensions.Internal.ExtensionEditorHostBase`1.InitializeNew(Type extensionType) +190
Inedo.BuildMaster.Web.WebApplication.Administration.Environments.EditServer.CreateChildControls() +195
System.Web.UI.Control.EnsureChildControls() +189
System.Web.UI.Control.FindControl(String id, Int32 pathOffset) +40
System.Web.UI.Page.ProcessPostData(NameValueCollection postData, Boolean fBeforeLoad) +313
System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint) +2773

Version Information: Microsoft .NET Framework Version:4.0.30319; ASP.NET Version:4.0.30319.17929

Product: BuildMaster
Version: 4.1.6

When you say dummy server, you mean the "Dummy Agent" in the Dummy extension? Very likely could be a bug in that extension; we primarily use that to test extensibility points. I assume this is for testing multi-server functionality and the like?

But in any case, I don't think the Dummy Agent will provide any useful functionality; you probably want to create additional Local agents. This can only be done via the API / Database directly.

Just look at how server ID=1 is configured, and add as many additional servers as you'd like (just make sure to use different names).

Yes, it's from the Dummy extension. When I click the "Add Server" button on the Servers page, it lets me choose an agent type -- self-hosted, IIS-hosted, SSH-based, or Dummy Agent.

I was hoping to use dummy servers as stand-ins for real servers that don't (yet) exist so I could create my deployment plan before the servers exist. Then, once they exist, I would just point the deployment steps to the real servers.