This is indicating that you don't have Analyst installed on the computer you are trying to use to export your method. Are you feeling that Skyline is mistaken and you actually have Analyst installed? Skyline checks the registry for a key that Analyst sets there in order to find the Analyst libraries it needs to export a SCIEX method.
You can solve this issue by either copying your file to an instrument control computer (with Analyst installed) and exporting your method there, or you can install Analyst on your non-instrument computer.
Skyline cannot export a SCIEX instrument method without an Analyst installation on the same computer. But, let us know if you think Skyline is just not finding an installation you believe you can find on the computer in question, and we can start digging into the registry keys on your computer to understand why they are not enough for Skyline to find the installation.