SharePoint Pain

Sometimes the Office Online service (WACSM) fails to start from the Services console and PowerShell with this error: The Office Online service on Local Computer started and then stopped. Some service stop sutomatially if they are not in use by other service or programs.   In the Windows Application event logs and as well as sometimes in the Trellix event logs, the following error appears:   ExP:DEP Stack Blocked an attempt to exploit C:\WINDOWS\SYSTEM32\INETSRV\W3WP.EXE   In addition, the Windows Application event logs show:   Service cannot be started. System.InvalidOperationException: The certificate has not been specified .   Even with the Office Online service not running in any of the farm members, OOS still renders Office documents, which is strange. As expected, however, it won’t let you run any Office Online PowerShell commands (e.g. Get-OfficeWebAppsFarm). Diagnosis   Case 1 : A certificate with the same Subject name is found in the Personal Certi...

Symptoms When one tries to open an Office Online document, SharePoint gives the “ Sorry, something went wrong ” error message with a Correlation ID. All Office Online Server members in the farm work fine via https://<officeonlineUrl>/op/generate.aspx. However, the associated Correlation ID on the SharePoint ULS shows " System.TimoutException: The open operation did not complete within the allotted timeout of 00:01:00 ", and it stems from SPApplicationSecurityTokenServiceClient : Diagnosis IIS shows  SecurityTokenServiceApplicationPool is running, but it malfunctions according to the Windows event logs.  Remedy Recycle the SecurityTokenServiceApplicationPool on the identified server in ULS (highlighte):

Symptoms Office Online Server fails to open Office documents and leaves this error in the Office Web Apps event logs:   System.ServiceModel.Security.SecurityNegotiationException: Could not establish trust relationship for the SSL/TLS secure channel with authority '<servername>:809'. ---> System.Net.WebException: The underlying connection was closed: Could not establish trust relationship for the SSL/TLS secure channel. ---> System.Security.Authentication.AuthenticationException: The remote certificate is invalid according to the validation procedure.     Diagnosis IIS sites have the unsupported HSTS configuration: HSTS ==> “ Redirect Http to Https ” It needs to be enabled for the IIS security, but it breaks the Office Online functionality. Remedy Uncheck (disable) the “ Redirect Http to Https ” checkbox for both HTTP80 and HTTP809 sites: The “ Enable ” and “ IncludeSubDomains ” options do not cause the outage. Therefore, they can be left enabled.  No ...