Incorrect username or password

IS the check compatible with ESXi 6.0?
I am getting the following error
Error: Cannot complete login due to an incorrect user name or password.
when the password is completely right , since I can use it with vmware-cmd through vCLI 6 on the same nagios host (which is a prerequisite to make this check work)
My .txt file is in format:
IP root password

and I have 9 servers defined in it, tried them all in the check, all get the same error