Forum Discussion
Email subscriptions random failues
This ended as a support call to Microsoft.
It turned out that the report server process was not reading the exension dlls and a later update of the March build fixed the scheduling problem and it is also fixed in the August release.
I'm having a similar issue. Lots of paginated report subscriptions and they all worked fine on Mar 2018 PBI RS. Recently upgraded to Aug 2018 PBI RS and now the subscriptions intermittently fail with errors like below, which is clearly a permissions issue. However, re-running it without changing any permissions solves the problem....atleast for awhile.
Failure sending mail: The permissions granted to user '' are insufficient for performing this operation.Mail will not be resent.
I got "The Delivery extension could not be loaded" randomly.
But I got this as well, enable debug tracing for the report server (https://docs.microsoft.com/en-us/sql/reporting-services/report-server/report-server-service-trace-log?view=sql-server-2017) and double check the mail setup that the account has relay permissions on the smtp server and get the SMTP admin to check the mail server logs. Most likely the SMTP server is blocking you from sending email