AdWords manager account required
Re: AdWords manager account required
An Adwords Manager account ( formally known as MCC) allows a single email to be used to work with other adwords accounts ( ie clients accounts by adding them under your umbrella account}
More About MCC/ Adwords Manager Accounts
Adwords in general uses an Email address and ties that to the account, Only one email per account. So if you have used the Email to assocaite to an individual adwords account, that email is essential burned, and can not be used for any other adwords account.
Hence the MCC or Adwords Manager account.
basically it is telling you your email is already tied to an Adwords account and wants you to either provide a new one, make an MCC/ Adwords manager account, etc to follow through the process.