Article ID: 129087, created on Jul 6, 2016, last review on Jul 6, 2016

  • Applies to:
  • Operations Automation 6.0


O365 users are not syncing. Corresponding user is absent in MOP but present in OA, synchronization script fails after a ~5 minutes with Unknown error occurred:

A communication timeout is being reached (Unknown error occurred)

OA executed the following query and got the result only after 1 hour:

Jul  2 09:40:46 : DBG [rest:219937 1:24116:dc906b70 SAAS ]: [ RDBMS] Prepare     [0xe52b74e8]: SELECT "id" FROM "aps_resource" WHERE "uid" = $1 FOR UPDATE
Jul  2 09:40:46 : DBG [rest:219937 1:24116:dc906b70 SAAS ]: [ RDBMS] Execute     [0xe52b74e8]: 503d9923-7589-4895-9bf0-f3d46ac07468
Jul  2 10:42:00 : DBG [rest:219937 1:24116:dc906b70 SAAS ]: [ RDBMS] Fetch     [0xe52b74e8]: 166559

Timeout has been reached for the request at APS endpoint side and following error was shown:

2015-07-02 09:45:46,707 [  35] ERROR aps_endpoint: Outgoing request 6c613197-5b3d-45ad-a998-c9caa8e63cbe: response error
System.Net.WebException: The operation has timed out
at System.Net.HttpWebRequest.GetResponse()

As a result unknown error was displayed in CCP.


Deadlock happened between aps_resource and aps_account_context tables. Both tables were locked FOR UPDATE. The issue has been reported to the development team in scope of the request APS-27909: Subscription creating via API: PSQLException: deadlock detected and fixed in OA 6.0 update 5.


Please update your environment to OA 6.0 update 5 or later. As a workaround it is necessary to restart pem, pau and PostgreSQL services on OA Core server.

Search Words

Both tables were locked FOR UPDATE


O365 sync

Unknown error occurred


The operation has timed out

O365 users are not syncing

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