Cannot add server to OAB distributionlist

The problem is that you cannot add a server to the OAB distributionlist, when one of the CAS (Client Access Server) are offline.

When opening the OAB, you'll wait for a LOONG time, and then get an error.

Now this is a rather large installation, but only one of the servers are offline:


When trying to press the "Add" button you'll get the following error:

Well the only solution, besides turning the machine on, that is turned of, is to set it with Powershell.

The thing to notice, is if you set the offline addressbook by using:
Set-OfflineAddressBook -Identity "\Default Offline Address Book" -VirtualDirectories "NEWSERVERNAME\OAB (Default Web Site)"
...then this NEWSERVER will be the only server in the offline addressbook's virtual directory!

So what I did, was to grab the existing Vdirs, and add the new one like this:
get-offlineaddressbook | fl
Then copy the existing  "VirtualDirectories"
They will be like this:
{SERVERNAME1\OAB (Default Web Site), SERVERNAME2\OAB (Default Web Site)}
Then run:
Set-OfflineAddressBook -Identity "\Default Offline Address Book -VirtualDirectories "SERVERNAME1\OAB (Default Web Site)", "SERVERNAME2\OAB (Default Web Site)","NEWSERVERNAME\OAB (Default Web Site)"
Notice the way I put the quotes. I didn't think it was the obvious way to do it, but it works :-)

If you only got one OfflineAddressBook you can run:
(you wont need to enter the identity)
Get-OfflineAddressBook| Set-OfflineAddressBook -VirtualDirectories "SERVERNAME1\OAB (Default Web Site)", "SERVERNAME2\OAB (Default Web Site)","NEWSERVERNAME\OAB (Default Web Site)"




The errors in text:
Error found when loading objects, please use command-line to query or edit full list. Error:
The task wasn't able to connect to IIS on the server SERVERNAME. Make sure that the server exists and can be reached from this computer: The RPC server is unavailable.
It was running the command: 'SERVERNAME\OAB (Default Web Site)' | Get-OabVirtualDirectory.

An IIS directory entry couldn't be created. The error message is The remote procedure call failed and did not execute.
HResult = -2147023169 It was running the command 'Get-OabVirtualDirectory'