I had similar issues, eventually i found out that the External Role actually 
needs to be a group name that becomes the Security Admin grp for the console. 
Create a group in OU=IT,OU=Branches,DC=domain_name,DC=com and add yourself to 
it. Use the friendly group name in this field, not the LDAP path to the group.

--------------------

In next page in External Role field I entered my account in uppercase: 
JSAZONOV. Pressing the <<Next>> button I have error message "External role is 
invalid". 
I tryed to enter my account name in different formats: jsazonov, 
jsazonov@domain_name.com, domain_name/jsazonov in lowercase and uppercase - but 
it always failed .I always have error message "External role is invalid".

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