Lightroom Mobile cannot install on a regular Mac or Windows computer. Lightroom Mobile is designed to work on mobile operating systems such as Android and iOS. What is it that makes you think Lightroom Mobile has been installed?
Thanks for the response.
Well, because Lightroom is offering me a trail period of 30 days for the Lightroom mobile (CC) version of Lightroom 6.
I do not want this, just use my offline stand-alone version of this software.
Also I do not understand why this happens after entering the requested serial number in the installation proces.
Lightroom 6 includes a 30 day trial of Lightroom Mobile. Lightroom Mobile is an application that can be installed on your IOS or android mobile device, and then you can synchronize collections in your desktop Lightroom. Those collections will then be accessible from your mobile device. The message you are seeing is telling you that you have 30 days remaining in your trial version of Lightroom Mobile. If you don't want to see that then click on the identity plate and turn off synchronizing. In case you are not familiar, the identity plate is what you have included a screenshot of.
Thank you. This solved my problem.
This was for me a very confusing Adobe software install.