Had the typical problem syncing Quicken (2017) with Voya. Online instructions at Voya were either out of date or not available. I called and they instructed me to do this - and it solved my problem:
Your user name is whatever your website user name is AND @ [your plan name]. For example, if you work for Aetna, and your user name is your email, the Quicken login would be:
John.Doe@gmail.com@Aetna. If your user name is not an email, use it and the
@[plan], so JDoe123@Aetna. If you work for Booz Allen, it'll be username@ECAP
Then use your regular online password.
Worked like a charm!