KB40789 - Unable to connect to exchange using ActiveSync resulting in multiple "Reason cannot connect (callback)" entries in the user access log

This article describes an issue where end user are unable to connect to exchange using ActiveSync resulting in multiple "Reason cannot connect (callback)" entries in the user access log.

When an end user attempt to connect to exchange using ActiveSync, the following message may appear multiple times in the user access logs:

2016/11/14 11:27:57 - WebRequest Failed : Host: XXXX.acmegizmo.net, Request: /Microsoft-Server-ActiveSync?User=XXXX
&DeviceId=XXXX&DeviceType=iPad&Cmd=Sync Reason cannot connect (callback)
2016/11/14 11:27:58 - WebRequest Failed : Host: XXXX.acmegizmo.net, Request: /Microsoft-Server-ActiveSync?User=XXXX
&DeviceId=XXXX&DeviceType=iPad&Cmd=Sync Reason cannot connect (callback)

 

This issue can occur when one of the following conditions is true:

• Web feature is not enabled on the corresponding role
• Pulse Connect Secure (PCS) device is having connectivity issues to the backend exchange server

To resolve this issue, perform the following steps:

1. Login to the admin console
2. Navigate to Users > User Roles > [Role name assigned to ActiveSync] > General > Overview
3. Under Access Features, select the checkbox for Web

4. Click Save Changes

If the problem persists, take a tcpdump and replicate the issue to confirm if there is a network connectivity issue between the PCS and exchange server.  If further assistance, please open a support case at https://my.pulsesecure.net including the tcpdump and user access logs.