New Post: Open Other Mailboxes From GAL - Long Time required

Hello,

I have a problem with a long time required to open other Mailboxes from GAL.
A software vendor sold us a software which connects our telephone-system to the exchange-server. So when a telephone call is comeing, the software looks to my personal contact folder in outlook and shows me, which customer,... is calling.
The software was fine with exchange 2010. Now we've upgraded to exchange 2013. Since then, the automatic search needs a very long time to show me a result. We have look with the development of the software a very long time and they tested with mfcmapi. We've done the following steps:

• log on to the windows sever with the accoutn under which the telephone-software ist running
• open mfcmapi.exe (Version 15.0.0.1042)
• click "Session - Logon" (take the profile which the developer created
• click "MDB - Open other mailboxes - From GAL"
• select any user
• click "ok"
  Then the developer told me that a "normal" system would take 1 or 2 seconds. But our systems take 8-15 seconds to show me the result.
  

Now my question: Is there any solution to solve my problem?

Thank you very much and have a nice weekend!
Holger