Hi,
When you say "used a macro in the template" do you mean on a setting of a webpart placed on a template? Or do directly in the layout of a template?
If signing macros (as Joshua suggested) doesn't help, you might want to look at macro debugging:
https://docs.kentico.com/display/K82/Debugging+macros
This might point you in the right direction of the error.
Greets,
David