Group Series 500 - Unable to retrieve all contacts from Skype for Business directory

Hi,

I'm having trouble retrieving all contacts from a Skype for Business directory using the globaldir API command.

By searching an empty string like this:

globaldir ""\n

I can retrieve all the contacts from an LDAP directory.  However if my RealPresence Group 500 is set up with a Skype for Business directory server, searching an empty string returns nothing.

A hacky work around I currently have is to search every letter, and every number like so

globaldir a\n
...search the alphabet
globaldir z\n
globaldir 1\n
...search 1-9
globaldir 9\n

But this still somehow misses some contacts in the directory. For example sending the command

globaldir a\n

returns nothing, even though there are many contacts that start with the letter A.

I've tried to use the range option for the globaldir command, but it yields nothing as well.

I'm using a Polycom RealPresence Group Series 500 running on software version 6.1.5 (since 6.1.6 is broken).

Any help would be much appreciated.

Thanks,

James