When customer upgrade firewall from v1 to v5, it shows alarm as follow, customer can't upgrade successfully.
Customer want to upgrade from V100R001C20SPC700 toV500R001C60SPC300, it can't upgrade directly, it must upgrade from transit version in between to be able to Upgrade to Highest version
firewall can't upgrade from V100R001C20SPC700 toV500R001C60SPC300, it must upgrade from transit version.
Upgraded the firewall as following path V100R001C20SPC700 -->V100R001C30-->V500R001C30SPC100-->V500R001C60SPC300.
Then Upgrade is successfull after following this Path