Applies to NetAppp E-Series NetApp SANtricity OS Issue Error message after uploading the controller OS software and NVSRAM in Upgrade Center:Cannot Perform Upgrade Operation - An unkown issue occurred...Applies to NetAppp E-Series NetApp SANtricity OS Issue Error message after uploading the controller OS software and NVSRAM in Upgrade Center:Cannot Perform Upgrade Operation - An unkown issue occurred while performing the upgrade operation. Please try again The upgrade fails no matter how many times it is attempted even after a restart of the controller