Thanks to a system restore on my Windows 8 machine to try fix some issues, I now end up with a host of new errors. Two sets of these errors are seeing the following messages when I start the Task Scheduler:
"Task microsoft compatibility appraiser: the task xml contains a value which is incorrectly formatted or out of range"
"Task license validation: the task xml contains a value which is incorrectly formatted or out of range."
After some googling, I find the following suggested fix (https://www.kapilarya.com/the-task-xml-contains-a-value-which-is-incorrectly-formatted-or-out-of-range-windows-10). I was able to get rid of the error messages after following the instruction, but my machine is still unstable and at least one of the continuing issues are related to the "Task license validation" tasks. So, use the following with care.
To eliminate the type of error messages noted above when starting the Task Manager, run regedt32 and go to the following registry key:
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Schedule\TaskCache\Tree
You should export/backup the relevant keys and back it up in case things go wrong and you have to restore them. Then, search for the name of the task that cause the error and delete the key.