Unable to retrieve user when testing remote directory configuration (AD Integration)

[PF]

I am getting "user abc does not exist" when testing a connection to MS Active Directory.

My AD integration settings are:

BASE DN: OU=userAccounts,DC=ABC,DC=COM
Additional User DN: Empty
Additional Group DN: Empty

If I remove the OU reference, I can connect and test without issue.

BASE DN: DC=ABC,DC=COM
Additional User DN: Empty
Additional Group DN: Empty

I need to keep the OU=userAccounts reference in order to limit what is getting returned from AD.

No I need to modify the default User Object Filter fround under "User Schema Settings"?

User Object Filter = (&(objectCategory=Person)(sAMAccountName=*))

User Name Attribute = sAMAccountName