The MAPI subsystem has indicated that the Global Catalog Server
dfwsrv1.ad.corp.expertcity.com which is used to resolve addresses for message submission cannot be reached, and that it has switched to using Global Catalog server dfwsrv1.ad.corp.expertcity.com. Unity will continue to function using this newly selected Global Catalog server and will not automatically switch back to the original one. If Unity does not have a dedicated connection with sufficient bandwidth to the newly selected server, then there may be significant delays in Exchange access by Unity. Please verify that Unity has a good connection to the new Global Catalog for proper functioning.
My unity box seems to be functioning perfectly well otherwise. I'm not sure why it is looking to that server as a global catalog server. From the DCGC reconnect toll as well as DOHPropTest, it is looking at a different Domain Controller and Global Catalog server.
Are you getting this error “Installer User Interface Mode Not Supported. The installer cannot run in this UI mode. To specify the interface mode, use the -i command-line option, followed by the UI mode identifier. The value UI mode identifiers...
The below trick might come handy when you have to add a new node to a cluster but you don't have or is unsure of the security password for the publisher. This procedure has been around for ages.
1) Login into the CLI of the Publisher.