Iphone and ipad Lync Client Randomly cannot sign in to Lync 2013 Server

Question

I have a Lync 2013 environment that will allow all clients to connect from inside and outside of the network except for ios devices. iOS devices are sometimes able to connect and sometimes not. When they are not able to sign in they receive a message stating,
"An Error Occurred in Lync. Please retry. If the problem persists, contact your support department"
I have run tests using the Microsoft Remote Connectivity Analyzer and all tests come back green.  I have also used the Lync Connectivity Analyzer and get the results below:
Starting Lync server autodiscovery
Starting automatic discovery for secure (HTTPS) internal channel
Server discovery failed for secured internal channel against
https://lyncdiscoverinternal.earenfroe.com/
Starting automatic discovery for unsecure (HTTP) internal channel
Server discovery failed for unsecured internal channel against
http://lyncdiscoverinternal.earenfroe.com/
Starting automatic discovery for secure (HTTPS) external channel
Server discovery succeeded for secure (HTTPS) external channel against URL
https://lyncdiscover.earenfroe.com/
Starting automatic discovery for unsecure (HTTP) external channel
Server discovery failed for unsecured external channel against
http://lyncdiscover.earenfroe.com/
Starting the requirement tests for Lync Mobile 2013 App
Starting tests for Mobility (UCWA) service
Completed tests for Mobility (UCWA) service
Your deployment meets the minimum requirements for Lync Mobile 2013 App.
Anyone have any suggestions on where to go next?  Troubleshooting an intermittent connection issue that only affects one mobile platform is tough...especially when all the testing tools say everything is configured correctly :)
Thanks in advance!
Tom

Answer 1

I have the same problem, and we have netscaller as revrse proxy solution and we have the required records created for mobility.
with lync2010 mobility it is working fine, but with lync 2013 mobiltity we have intermittent issue with error e2-3-33 error
raghu
I had the same problem (e2-3-33 on mobile devices at random times) and it turns out it was McAfee antivirus causing the UCWA service to crash repeatedly. The workaround for it is outlined in the below blog entry I found as well as the below Microsoft document.
Long story short you want to run  follow the steps outlined in the workaround section below (I copied it from the linked MSFT document)
http://support.microsoft.com/kb/2997513
http://lynclounge.blogspot.com/2014/07/lync-mobility-issues-event-ids-1309.html
WORKAROUND
he following procedures must be performed on all Lync Server 2013 FE server and Director Lync 2013 server roles. To
perform these procedures, first open a command prompt as an administrator.
Windows Server 2008 R2
On the Start menu, type cmd.exe in the Windows search feature, and then press Enter.
Right-click cmd.exe, and then click Run as administrator.
Windows Server 2012
Press the Windows key to access the Start page.
Use the Windows search feature to locate cmd.exe.
Right-click cmd.exe, and then click Run as administrator.
In the Command Prompt window, follow these steps:
Navigate to the %install drive%:\Windows\System32\inetsrv> directory prompt.
Enter the following command, and then press Enter:
appcmd set config /section:applicationPools /[name='LyncUcwa'].recycling.disallowOverlappingRotation:true
Enter the following command, and then press Enter:
appcmd set config /section:applicationPools /[name='LyncUcwa'].processModel.shutdownTimeLimit:0.00:00:30
To confirm the changes from steps 2–3, enter the following command, and then press Enter:
appcmd list apppools lyncucwa /config
The following information should be returned to the console to confirm the update to the LyncUcwa application pool
settings:
<add name="LyncUcwa" autoStart="true" managedRuntimeVersion="v4.0" managedPipelneMode="Integrated" startMode="AlwaysRunning">
<processModel identityType="NetworkService" idleTimeout="00:00:00" shutdownTieLimit="00:00:30" />
<recycling disallowOverlappingRotation="true">
<periodicRestart time="00:00:00">
<schedule>
</schedule>
</periodicRestart>
</recycling>
<failure />
<cpu />
</add>