When trying to run a report from Mariner or from the Report Manager, an error of the form: "Execution '...' cannot be found (rsExecutionNotFound)" occurs. The same error occurs if the report is run from within Mariner or directly from Report Manager. The log.txt file is not being written to the REPORTING
Usually this is set to the "Network Service" account or the "Local System" account. Whichever account it is make sure that account has permissions to write to the install folder where either Mariner or Agile is being installed to. By default the products will install to the appropriate folder on the C:\Program Files\Serena folder.