RTD formula evaluates to #N/A in Excel

If you use a formula that includes the RTD function in Microsoft Excel, the formula may evaluate to #N/A.

This issue occurs if any of the following conditions are true:

• The RTD server returns unexpected information, either because the Topic ID is wrong or the array returned by the server contains extra, unexpected information.
• The RTD server fails.
• The RTD server is not registered on the computer.
• The RTD server returns "-1" for Topic Count.
• The RTD server returns "-1" for Heartbeat.
• The RTD function is waiting for the server to return information. If the RTD server is running over a slow connection, or the server establishes other connections before returning results to Excel, #N/A remains in the cell until Excel receives results.

To resolve this issue, use the following methods, in the order that they are presented. Go to the next method in each case only if the current method does not resolve the issue.

• Stop and then restart the server.
• Exit and then restart Excel.
• Debug the server.

The RTD function, or the formulas that use it, evaluate to #N/A for a variety of reasons. It may be that the RTD server has failed completely, that it has returned an invalid Topic ID, or that some other error has occurred in retrieving data from the array of values returned to Excel by the RTD server.

Because Excel is not able to distinguish between these errors, the #N/A value is displayed in the cell that contains the RTD function in every case, and the #N/A value appears in all cells receiving data from the server in question, regardless of the Topic used.

For more information about the RTD function, click the following article number to view the article in the Microsoft Knowledge Base: For more information about how to set up an RTD server, click the following article number to view the article in the Microsoft Knowledge Base: