Step by Step easiest solution:
- Open Task Scheduler(TS) in Windows 2008 or 2012
- Select top node on the left pane named "Task Scheduler(Local)"
- Click on "ACTION" Menu on the top , and select "Connect to Another Computer..", Key in the IP address or the name of your 2003 server and click OK.
- Click on the 2nd Node on the left pane named "Task Scheduler Library", you might get a message box with info "Copyconfig.job" no longer exists...just ignore it and click OK, you should see all your 2003 server scheduled jobs on the right pane.
- Select the 2003 tasks one at a time , then right click and select export...export it to a known location.
- Once you are done exporting all the 2003 tasks, close the Task Scheduler and reopen it.
- Click on the ACTION menu, select Import and import from the exported location One Job at a time , make sure to user account under whom the jobs needs to be run in the new server.
Screen shots here https://social.technet.microsoft.com/Forums/windowsserver/en-US/467e5cab-2368-42de-ae78-d86b644a0e71/transfer-scheduled-tasks-to-server-2008?forum=winserverMigration