UCWA events in Skype for Business Server

Summary: Learn about the Unified Communications Web API (UCWA) in Skype for Business Server.

Skype for Business Server uses the Unified Communications Web API (UCWA) for a number of purposes, from accessing Microsoft Exchange for contact searches to updating presence for mobile clients.

UCWA will write records of operational behavior as event types Informational, Warning, and Error. The following table describes the events that can be written by the UCWA components.

Event ID Event type Summary Cause and resolution
20001
Informational
UCWA initialized
N/A
N/A
20002
Error
UCWA encountered an unexpected exception during initialization
An unexpected error has occurred during initialization
Examine the exception details in the associated event log entry to determine the possible cause
20003
Error
UCWA encountered an unhandled exception
An unhandled exception happened
Restart the server. If the problem persists contact product support
20004
Error
Cannot access Exchange for HD photo
Connection to Exchange is not available
Make sure the connection to Exchange is available
20005
Informational
Recovered from failing to access Exchange for HD photo
N/A
20006
Error
Cannot access Exchange for contact search
Connection to Exchange is not available
Make sure the connection to Exchange is available
20007
Informational
Recovered from failing to search contact in Exchange
N/A
20008
Warning
Attempt to subscribe more than the allowed presence subscriptions per application
Attempt to subscribe more than the allowed presence subscriptions per application
Check the clients for unnecessary subscriptions
20009
Warning
Attempt to subscribe more than the allowed presence subscriptions per batch
Attempt to subscribe more than the allowed presence subscriptions per batch
Check the clients for unnecessary subscriptions
20010
Error
Cannot retrieve inband data
Cannot retrieve inband data
If the problem persists contact product support
20011
Error
Cannot subscribe presence
Cannot subscribe presence
If the problem persists contact product support
20012
Error
Failed to register endpoint
Failed to register endpoint
If the problem persists contact product support
20013
Error
IM MCU is unavailable
IM MCU is unavailable
See whether IM MCU is running
20014
Informational
Recovered from failing to connect to IM MCU
N/A
20015
Error
AV MCU is unavailable
AV MCU is unavailable
See whether AV MCU is running
20016
Informational
Recovered from failing to connect to AV MCU
N/A
20017
Error
AS MCU is unavailable
AS MCU is unavailable
See whether AS MCU is running
20018
Informational
Recovered from failing to connect to AS MCU
N/A
20019
Error
Data MCU is unavailable
Data MCU is unavailable
See whether Data MCU is running
20020
Informational
Recovered from failing to connect to Data MCU
N/A
20021
Error
Cannot join IM MCU
Cannot join IM MCU
See whether IM MCU is running
20022
Error
Cannot join AV MCU
Cannot join AV MCU
See whether AV MCU is running
20023
Error
Cannot join AS MCU
Cannot join AS MCU
See whether AS MCU is running
20024
Error
Cannot join Data MCU
Cannot join Data MCU
See whether Data MCU is running
20025
Error
Cannot access active directory for photo
Connection to active directory is not available
Make sure the connection to active directory is available
20026
Informational
Recovered from failing to access active directory for photo
N/A
20027
Warning
Cannot deserialize
Cannot deserialize
If the problem persists contact product support