This error can be detected by the entries “VMapManager2: could not load …” in the Server.log file, as well as in the game world, the location of the characters is displayed as “Unknown” and, accordingly, some criteria related to locations are not fulfilled.
This error is corrected by copying all files from the “Buildings” directory to the “vmaps” directory.
In Linux, this can be done with the commands:
cd /home/trinity/server/data/Buildings
cp -r * /home/trinity/server/data/vmaps
I also noticed this problem on Linux Ubuntu systems where the home directory of the main user where the server was located was encrypted. A quick solution is to create a new user without encrypting the home directory with the command “sudo adduser NAME” and launch the server from its directory on its behalf.