WHM cPanel login - xfercpanel - not working

I'm having difficulty using the xfercpanel link in WHM to log into a few client domains that have just been moved from another server. When I click the cPanel login link in my WHM for any of these sites, the login fails and I'm shown the typical "Login Attempt Failed!" screen.

Is there something I need to do to sync up the passwords for the sites I've transferred across?

 

I think I may have resolved the issue in my case anyway. These accounts were under the ownership of a reseller account which I hadn't yet moved across. By changing the ownership to a reseller account that does exist on the server, I was able to log in. I'll soon be able to verify whether this was the cause for me when I move the reseller account across and test one of the other accounts

 

I can confirm my problem appeared to be due to the fact that I didn't have a valid 'owner' of the accounts in question. As soon as I moved their master reseller account across, I was able to access the cPanel via the link in the root WHM.