KTA Decision Node Unexpected Character

Summary

If we add a decision node to a map and then try to validate the condition, we might get an error like the one shown below:

The cause of this error can be that a variable ID has a special character in its name e.g. ' . * ( )

As we can see here, Client's name has an apostrophe in the ID

To workaround this issue, you must remove the variable from all nodes within the process, delete the variable and recreate it without the special character

A bug has been raised for this issue and the current fix is assigned to 7.3