Unable to add standalone host to vCenter

[ABEIQ]

Hi All, 

Hoping ive put this in the correct discussion location, Ive run into an extremely weird issue regarding adding standalone hosts to Vcenter. I have done quite a bit of searching and have come up short. 

I am unable to add any host to vcenter anymore, i could originally add a few, then all of the sudden i am unable to, when adding a standalone host, it connects, accept the cert, etc etc, then once the wizard is done, the tasks list shows that the host is being added, it hangs up at 0% and then the below message is shown. 

"Could not connect to the host due to an invalid username and password combination"

This is extremely weird because the host clearly connects during the wizard as i am able to accept the certs? 

Below are the troubleshooting steps i have performed; 

- Rebooted hosts 

- Rebooted Vcenter 

- Checked time and certificate validity

- tried to add multiple different hosts 

- tried different browsers 

- changed complex passwords to simple ones just in case my password was the issue 

Any suggestions? 

[ABEIQ]

did some troubleshooting with another bloke, looks like the robo sites that i am having issues with happen to have a cellular internet connection. sites that have dual internet connections have been moved to using a fixed line service and vcenter is able to connect, looks like some cellular carrier voodoo.

Thanks for the input guys

[amansapra19]

Please check the Build version of vCenter Server and ESXi hosts. This generally happens if your ESXi host is on a newer version than vCenter Server.

ESXi Build Versions: https://kb.vmware.com/s/article/2143832

vCenter Build versions: https://kb.vmware.com/s/article/2143838

[bryanvaneeden]

AFAIK, showing the certs is not accepting the user credentials. I've seen it multiple times that I could see/accept the certificates, but the user credentials were wrong.

Good that it's all resolved!