I am already a VCP 6.0 , but would like to upgrade to VCP 6.5, by passing the 2vo0622d exam.
My question is, do you have complete a mandatory course before taking this exam?
Thanks in advance
No, you only need to take the exam. See "Path 1" in "Existing Candidate Requirements" at VMware Certified Professional 6.5 - Data Center Virtualization
PS: I assume that the VCP6 certification has not expired yet.