A scheduled task consecutively failed on one of my servers. In the Task Scheduler I found out the error code was 2147943726.
The cause was quickly found: the task was running with a user credential. But because the user had changed his password, the service did not run successfully anymore.
So basically: an incorrect / changed password is the cause of error value 2147943726
The solution was quite simple: Create a service account that is dedicated to the scheduled task. Make the password “never expire“. Once I set this up, the problem was solved and will probably never return :)