I recently upgrade to Yosemite and now Endnote wont open at all. It never worked properly but I assume I now have to upgrade to 7?
I believe your assumption is correct. See http://endnote.com/kb/129914 (and http://endnote.com/kb/113230) for Mac OS compatibilty.
Note the Endnote is not yet compatible with Word 2016 (Mac or Windows) as ample threads on the forum will attest to. Thus we need to move to the new software. “Slowly I turned…step by step…inch by inch…,”
Leanne is correct. EndNote X5 is not compatible with OS X 10.10, Yosemite. For compatibility with that operating system, you would need to upgrade to EndNote X7. EndNote compatibility information can be found here:
http://endnote.com/product-details/compatibility
You may want to contact our Sales Team to find out your pricing options for upgrading: