Hi again 
For those who might run into the similar trouble - i am one step further and i will check if it causes further troubles - if not will soon close this ticket.
The problem maybe even at its beginning seems to be linked to the âUnreal IntegrationToolâ which seems to be outdated and not needed. This would explain, why the problem i experienced was somehow linked to the project environment at some point and looked in some lines of the output log like a fallback for some missing other part.
The last mentioned error ( âSetENVâ task VS )that after reinstallation and updating this magick.Net and microsoft.build NuGet packages appeared can be repaired by following: solution and seems to be bound to VS 2026 and the local app data of Unreal Engine.
After this a new error appeared - which was linked to the IntegrationTool:
Expecting to find a type to be declared in a module rules named âVisualStudioToolsâ in âUE5Rules, Version=0.0.0.0, Culture=neutral, PublicKeyToken=nullâ. This type must derive from the âModuleRulesâ type defined by UnrealBuildTool.
this can be fixed by deinstalling the IntegrationTool plugin + regenerating project files etcâŚ
In conclusion:
The NuGet versions which worked so far for me are :
- Magick.NET-Q16-HDRI-AnyCPU 14.14.0 only installed on the demanded check point
- Microsoft.build 17.11.48
⌠they might have again a short expiration time (LOL)
Maybe worth mentioning:
- the reposted suggestion of fixing âSetENVâ VS error using 2026 and setting the pathlength to a particular number did not fix the problem (and this only can be done in VS 2026)
- It was a BAD BAD BAD IDEA of repairing the VS-2022 installation: VS installer failed with an error that some UnrealEngine.msi could not be repaired and broke VS installation
- deinstalling VS 2022 DELETED: Epic launcher exe, any Unreal Engine Version installed on my system like here: https://developercommunity.visualstudio.com/t/PackageId:UnrealEngineV1;PackageAction:R/10910043