Scenario one:

• Create a group "A";
• Create two hosts "H1" and "H2";
• Create items for both hosts, so that when copying a trigger from another host, these items exist and trigger could be created;
• Choose another group and host and pick one trigger to copy;
• Select destination group "A";
• The error message says that the trigger already exists, but it's not true.

Scenario two:

• Create a group "A";
• Create a template "T1" and a host "H1";
• Link them together;
• Create an item on template, so that when copying a trigger from another host, that item exists on host and template, and trigger could be created;
• Choose another group and host and pick one trigger to copy;
• Select destination group "A";
• The error message says that the trigger already exists, but it's not true.