QNAP released QTS version 4.4.1 around September 2019. Prior to QTS 4.4.1, Xeams was part of QNAP's AppCenter. Due to some reason QNAP has removed a few third-party applications from their latest QTS, including Xeams.
This does NOT mean you cannot use Xeams on QNAP.
Historically, there have been two packages for Xeams on QNAP:
Therefore, we recommend you download a Xeams package for QNAP from our website and use that instead. This package is fully supported by Synametrics Technologies, Inc. and works fine on QNAP.