We run on a Citrix environment do I need to make the registry change on every users computer or just the Citrix servers?

We're running Cyrstal Reports 2013 with Sage 100 in a Citrix environment. The users are logged into any one of 4 servers that connect to the MAS server. Where do I put the registry entry? Please be kind I'm not a networking person, I'm the data/systems/reporting analyst and am doing research on this before I bring it up to our network managers.

thanks,

Clare