as the reload has failed, its difficult to say why would have it failed as it depends on lots of factor, the first being a script error, or in your case, i think this QVW is to extract the data and when it ran the database was down or busy and Qlikview was not able to connect to the database. This could be one reason.
To monitor this, i would suggest you enable the Generate Log File option and also enable the option "Timestamp in LogFile Name" as this will create separate log files for each run, and this way you can verify the hostoric run details also.
The task failed again. As you suggested, I enabled "Timestamp in LogFile Name", and the log shows "General Script Error". But when I debug the script, there is no errors in script. I reran this task, and it reloaded successfully. Anyone has any idea why my task failed? Many thanks.
I exam-med all qvws that may run at the same time when this task is running. And found they are all independent. The only reason I guess is that a couple of large qvws start and end almost at the same time and they may compete limited source(like memory, cpu etc.) , which leads to this task failed to store its own qvd sometimes.