"Unable to connect to the Archvision Content Manager at the following address: 127.0.0.1:14931 Make sue that your RPC Content Configuration contains the correct address for your ArchVision Content Manager. You may need to check with your office administrator to obtain the correct information, or you can use the Scan feature to locate the ArchVision Content Manager."
RPC cells are not delivered by default with MicroStation, they come from Archvision, it is a standard message if a connection is not set up. This is a seperate database that needs to be set up with ArchVision itself.
Go the MicroStation help, select the 'Search' tab and enter "archvision" as the search. This gives more information and background to RPC Cells and how to connect to ArchVision. Also, there may be sample RPC cells that can be downloaded from the internet.
http://help.archvision.com/products/bentley-microstation/videos/
https://www.archvision.com/