Getting 3 compiler warnings before I even alter script

/Library/Frameworks/Mono.framework/Versions/5.12.0/lib/mono/msbuild/15.0/bin/Microsoft.Common.CurrentVersion.targets(5,5): Warning MSB3277: Found conflicts between different versions of “mscorlib” that could not be resolved. These reference conflicts are listed in the build log when log verbosity is set to detailed. (MSB3277) (3_project_Boost)

Does anyone know how to solve this warning?



Do you have multiple versions of Unity installed?

No, Only showing one in my application folder

I have a unity bug reporter

Ok, did you have Visual Studio installed at all prior to installing Unity?


If I delete both and reinstall will error go away

Out of interest, I take it you didn’t have these issues with the previous projects before Project Boost?

I would probably consider doing a complete uninstall and reinstall of Unity then. Not sure which version you have installed as you didn’t state, but I would go for the latest version. Often peoples reported issues are resolved with a reinstall, so this may be the quickest/easiest approach.

I can’t say for certain that the problem will go away, as we aren’t really doing much here to diagnose what has caused the problem or really even what the problem is, but it is going to be the quickest approach to trying to resolve the problem. If it works, great, if not, then further investigation would be required.

Cool, have the latest version. will try a reinstall . Should I also reinstall VS?

Visual Studio I would imagine was installed as part of the installation of Unity yes? e.g. you didn’t download/install it separately?

If they were installed together then remove together, if they were installed separately, remove separately - and then reinstall.

Did you have these issues with the previous projects?

No I installed separately . Thanks for the quick response.

Did you have these issues with the previous projects, or has it only just started occurring with this project?

No I think it was there in all, just noticed it now though. projects build

So these are just warnings and no preventing a successful build?



Sorry for the delay, was sorting my son out for bed.

Ok, so Mac also. Anything I’ve found online so far that comes close to the issues seems to also be on that platform, not sure how relevant that is.

These are obviously only warnings, so perhaps not the end of the world. You may find after a reinstall you have the same issue.

The messages mentioned about turning the logging verbosity on to full to see more details with regards to the specific reference, if the issue continues that may be worth trying.

You could also have a look at the References within Solution Explorer, your layout is considerably different to what I’m used to on a PC, I’m guessing its the pane on the left.

On that note, I think I’ve seen the non-expanded view before, e.g. it doesn’t show the solution as such, just the bits relavent to Unity if you have the Visual Studios Tools for Unity installed - do you have those installed?

As an example of the References within Solution Explorer, this is the view I am referring to;

I am trying a reinstall. I didn’t know unity came with VS, downloading another VS might have created the problem. Erased everything and am reinstalling.

There was certainly a version of Unity which also installed Visual Studio Community Edition, but we are in the realms of different OS than I am used to and I’ve not installed Unity in the original way for quite some time, I tend to use Unity Hub these days, I don’t recall seeing options for Visual Studio but equally I don’t really pay that much attention on the install as I’ve done it so many times.

If you uninstall both and then just install Unity, then goto Preferences / External Tools and see what is available under the External Script Editor drop down… if Visual Studio is listed then you certainly shouldn’t need to download another version;


The view will most likely look a bit different on your Mac :slight_smile:

ReInstall Fixed Problem.(Deleted Unity and VS) Mac Unity comes with VS. Downloading another copy of VS might of caused the warnings.

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