Look at the help or the manuals on this topic.
201 Range Check Error
Reported in the {$R+} state when:
1. index expression of an array is out of range.
2. attempted to assign an out of range value to a variable.
3. attempted to assign an out of range value for a parameter of a
procedure or function.
Since you fail to provide us any code to be able to spot this error
and help you, then you need to take what I stated directly out of the
manual and look at your code.