I've upgraded to the newest version of SD last week. Since then I'm experiencing problems because according to Windows -Programs and Features SD is installed on the server but when I login into JIRA i can't access the service desk and it says the tool is licensed but not installed. When I hit the install button next to the message it starts installing but suddenly stops. (see screenshot)
What version of Jira/Jira Service Desk did you upgrade to and from? Just by looking at your screenshot, I can see that you have Jira installed, and it looks like you have a Service Desk license, but if you are unable to complete the installation with the use of the "installeren" link, then there is something gone wrong here.
The version you came from is important because starting with Service Desk 3.2.x and above there is a required upgrade path that has to have been followed. This is only a problem if your Service Desk data has not yet been upgraded to a 3.0.x version or higher. This problem was commonly seen with users trying to upgrade their JIRA 6.4.x with Service Desk 2.5.x versions directly to the Jira 7.2.x and Service Desk 3.2.x or higher versions.
So if your service desk data has not yet been upgraded to a 3.0.x version or higher, we should stop this upgrade and first complete that upgrade. The catch with that is you can only install that version of service desk on a JIRA 7.0.x version. This minimum upgrade requirement is also noted in the JIRA Service Desk 3.2. release notes.
If you have already come from a 3.0.x version or higher, then I would like to see more of the JIRA_HOME/log/atlassian-jira.log file immediately after you try to install Service Desk with that installation button. That log file will tell us more information about why this is failing. But since you cannot upload that file here, I will create a separate support case where you can upload that file so we can investigate further.