When opening an SSRS reporting in a web browser the report generates the below error:

An error occurred within the report server database. This may be due to a connection failure, timeout or low disk condition within the database. (rsReportServerDatabaseError)

For more information about this error navigate to the report server on the local server machine, or enable remote errors

Possible Solution:

Run the below Query to find all Agent jobs linked the report (Both snapshot jobs and subscription jobs)

Step 1:

Run the below query to link agent jobs to Report that is timing out. This needs to be ran on your SSRS database instance.

SELECT NameOfReport = Cat.Name ,
Cat.Path ,
ReportID = Cat.ItemID ,
NameOfAgentJob = Sched.ScheduleID ,
LastExecutionTime = Cat.ExecutionTime
FROM ReportServer.dbo.Catalog Cat WITH ( NOLOCK )
LEFT JOIN ReportServer.dbo.ReportSchedule Sched WITH ( NOLOCK ) ON Cat.ItemID = Sched.ReportID
WHERE Cat.Name = 'Profit and Loss Reports';

SSRS Error 02

Step 2:

Check if there are multiple agent jobs with the same name (In the below instance there were 3 jobs with the same name highlighted)
All Agent jobs where empty (No schedules or Steps)

SSRS Error 03

Step 3:

Open the Management for the Report in a web browser and Cache refresh Options and delete the cached plan! (NOTE TO RECORD THE CONFIGURATION!)

SSRS Error 04

Step 4:

Delete the Agent jobs that had were linked to the cache snapshot if they were not deleted by deleteing the Cache snapshot in SSRS

Step 5:

Re-create the snapshot in SSRS

Step 6:

Check the report is running again