Whilst working through a patching session I noticed a standard edition front end server throwing Event ID 32134 every 10 minutes.

That’s new to me, so how do we resolve this?

Error Details

Event ID 32134

Event ID 32134
Source: LS User Services

Failed to connect to back-end database. Lync Server will continuously attempt to reconnect to the back-end. While this condition persists, incoming messages will receive error responses.

Back-end Database: rtcab Connection string of:

driver={SQL Server Native Client 11.0};Trusted_Connection=yes;AutoTranslate=no;server=(local)\rtc;database=rtcab;

Cause: Possible issues with back-end database.

Ensure the back-end is functioning correctly.


The error message does give a good clue as to where to start looking. The server cant connect to the backend database rtcab on the local server.

My weapon of choice is SQL Management Studio as it will allow me to take a peek at the suspect database.

Connecting to the local server and expanding the databases folder I notice the rtcab database stating that access is set to Restricted User).

SQL Restricted User


Not sure why this rtcab access has been locked, perhaps part of the update process that didn’t quite finish.

An easy fix, simply right click the database rtcab and select Properties. Navigate to Options.

Scroll down to the State section and change the Restrict Access to MULTI_USER.

Lync Backend Database

Even on a good day, error messages from SQL make me uncomfortable, BUT this particular issue has been comfortably sorted.