Recently I tried to update our SolarWinds EOC install from 2024.4.1 to 2025.2.1, a supported path, however this was not very smooth.
Keep in mind I had just installed this update from the same version on 2 module based installations the day before.
Backups etc. all taken beforehand.
When performing the install the SolarWinds installer prompted me with an error stating it was not able to stop the SolarWindsRecommendations service due to some permissions issue.
I've been a SolarWinds admin for over a decade and have not seen this error before. The service is locked for permissions at the system level. I was not able to use PSExec or any other utility to stop the service.
When I disabled the service from the registry at startup the SolarWinds installer STILL failed with the error. Even though in the screenshot below you can see the service is indeed not running.

Support was indeed useless to help remedy the issue. Even with the System Down priority ticket.
Nothing was present on Thwack or the Success Center to assist with the issue either. Permissions checker did not find any issues.
I ended up performing an uninstall of all SolarWinds products. At this point I was still met with the error that the service could not be uninstalled! Image below.

I had to ignore the error in the uninstaller and just let it complete. I then went and deleted the service from the registry, deleted the SolarWinds folders from the install directory and ProgramData. Then rebooted the server.
I was then able to install fresh the EOC update. Keep in mind support said they would call me back after an hour when we were unable to resolve the service permission issue. They had not called me back still at this point.
Services were up and running again after the configuration wizard ran.
Hopefully this helps someone else. As I could not locate any resources.