Hello and welcome to our forums,
We apologize for the delayed reply.
I think this could happen if you are trying to import a solution created with VS 2017 edition. Can you please send us by email to
support at advancedinstaller dot com your solution (the SLN file and all of its included projects - only the project files without the source code) so we can further test and investigate this?
To avoid this issue, as a workaround you can try to manually create from scratch a setup project. Have a look on our
"Professional" tutorial for a good starting point.
All the best,
Daniel