"Unable to process one or more commands" error message when you test a cube role in SQL Server 2000 Analysis Services (824419)

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256986 Description of the Microsoft Windows Registry

SYMPTOMS

When you test a role on a cube in Microsoft SQL Server 2000 Analysis Manager, and the cube includes a dimension that has dimension security defined, you may receive the following error message:

Unable to process one or more commands.
Connection to the server is lost.

You may also receive an error message that is similar to the following:

Unable to process one or more commands.
User-generated error - the dimension "<Dimension Name>" has no valid member. For more information, see your administrator.

CAUSE

This problem occurs because SQL Server 2000 Analysis Services does not permit dimension security on dimensions that reside in the Very Large Dimension Manager (VLDM). When a user first tries to access a dimension that resides in the VLDM, Analysis Services cannot access the replica dimension if dimension security is defined for that dimension.

When dimension security is defined for a role in Analysis Services, a replica dimension is created. This replica dimension includes only those dimension members that are accessible by that role. The replica dimension is created when the user first tries to access the dimension after a Multidimensional Expressions (MDX) query or a Microsoft ActiveX Data Objects (Multidimensional) (ADO MD) catalog operation is used to define dimension security.

WORKAROUND

To work around this problem, use one of the following methods:

Method 1: Log on to the computer where Analysis Services is installed, and then rename the VLDM executable file (Msmdvldm.exe). The Msmdvldm.exe file is located in the <installation drive>\Program Files\Microsoft Analysis Services\Bin folder. After you rename the VLDM executable file, Analysis Services cannot locate the VLDM executable file. Because of this, Analysis Services retains all the dimensions in the Analysis Services server (Msmdsrv.exe) process space, regardless of the size of the dimension.

Note When you rename the VLDM executable file, you do not have to monitor the size of the dimension regularly. You also do not have to increase the VLDMThreshold value to handle the dimension. However, VLDM is not available for all large dimensions, regardless of whether you define dimension security for the dimension.
Method 2: Increase the value of the VLDMThreshold Microsoft Windows registry entry so that the value is larger than the size of the largest dimension that is defined with dimension security. When you do this, other large dimensions that are not defined with dimension security can still be moved to the VLDM process space. To increase the value of the VLDMThreshold registry entry, follow these steps.

Warning If you use Registry Editor incorrectly, you may cause serious problems that may require you to reinstall your operating system. Microsoft cannot guarantee that you can solve problems that result from using Registry Editor incorrectly. Use Registry Editor at your own risk.
1. Open Registry Editor, and then locate the following registry key: HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\OLAP Server\CurrentVersion
2. In the right pane, locate the VLDMThreshold registry entry, and then change the value of the registry entry to the appropriate size (in bytes).
Note If you use this workaround, you may have to regularly monitor the size of the dimension that is defined with dimension security and update the VLDMThreshold value.

MORE INFORMATION

Analysis Services uses the VLDM to move large dimensions out of the Analysis Services server process space to improve the scalability of Analysis Services. By default, the threshold for large dimensions is 64 MB. You can configure the threshold for large dimensions by configuring the VLDMThreshold registry entry. Any dimension that exceeds the VLDMThreshold value is automatically moved to the VLDM process.