Be grateful if anyone could help me with the following as I seem to be running around in circles trying to find a solution to the following (v1.3.8)...

I have set up a coupon and need to create some restrictions but when clicking on the 'Restrict' button I get the following message

Sorry, your security clearance does not allow you to access this resource.

Please contact your site administrator if you believe this to be incorrect.

Sorry for any inconvenience.

(Real useful eh?)

had a google and this has been a noted issue before but no simple 'this is happening because...' or 'Just do the following to stop this...' is detailed.

Be very grateful is someone could help me out with some simple, plain english answer that a zen cart newbie would understand :-)

Thanks