Maybe it was your "...nice vbs script which cleans the event-log" that did you in.
I will tell you what I know about the 1053 with Task Scheduler, and you might want to look at your Event Log files and be sure they are not suffering the same affliction if this is the case with you Task Scheduler:
When trying to start the Task Scheduler Service, it looks like it is very slowly trying to start (and struggling), and then after a while you see a message like this:
Services
Could not start the Task Scheduler service on Local Computer
Error 1053: The service did not respond to the start up or control request in a timely fashion
One thing that can cause this error with Task Scheduler (and it gets stuck Starting) is if the Task Scheduler log file:
c:\windows\SchedLgU.Txt
is read only. Perhaps the file also corrupted somehow.
Using Explorer, Navigate to the c:\windows folder and locate the SchedLgU.Txt file, right click it and check the Properties. If the file is marked Read-only, uncheck that Attribute and click OK to save the changes.
You could also just delete the probably cluttered up SchedLgu.txt file unless you need it for something.
If your Task Scheduler Service is hung "Starting", you are going to have to reboot and then see if you can start the Task Scheduler Service and set the Properties Startup to Automatic.
When the Task Scheduler Service starts, if there is no log file, t will create a new log file but stuff will accumulate in if forever which can make troubleshooting Scheduled Tasks a tedious chore.
Y and Z