How to create a task(input the "ID" in the custom property )

[brolly33]

Computer ID decode (including the tricky bit swapping part) Solved by @SLB here:

How to output the "ID(computer id)" to text file or registry in own pc

You could use this to write the ID to a registry value regset "[HKEY_LOCAL_MACHINE\SOFTWARE\MyKey]" "ID"="{computer id}" Or how about converting the existing hexadecimal value from the registry? Q: hexadecimal integer (concatenation of characters (14;15;12;13;10;11;8;9;6;7;4;5;2;3;0;1) of (value "ComputerID" of key "HKEY_LOCAL_MACHINE\SOFTWARE\BigFix\EnterpriseClient\GlobalOptions" of registry as string)) A: 11698628 T: 0.298 ms I: singular integer

But I think your initial action script should have worked as well.
setting "BigFixID"="{computer id}" on "{now}" for client