Fsharp: Nightly build 15.4.1.17052601 won't open any projects

[piaste]

Updated to nightly 15.4.1.17052601 from the previous nightly and Visual Studio will now refuse to open any F# project:

Creating a new basic template results in:

This seems to be strictly a VS issue with .fsproj files; FSI, Ionide and Rider work as normal.

I've tried uninstalling both the nightly extension and the VS language support component, then rebooting, then reinstalling the extension, without effect.

Related information

• Operating system: Windows 10 v1703
• .NET Runtime, CoreCLR or Mono Version: NETFX 47
• Indications of severity: High?

[cartermp]

cc @brettfo

[brettfo]

Good catch, this is my bad.

The issue is that Microsoft.VisualStudio.LanguageServices, Version=2.3.0.0 could not be loaded. I've been developing locally with an internal 15.3 build and this obviously won't work for anybody else.

I'm testing the revert of #3062 locally (on the publically released VS :smile:) and once that's done I'll spin up another build.

ETA: 6 hours from now (official builds take a long time).

[realvictorprm]

Ah thanks @brettfo had a beginner today who struggled with exactly this issue! Will instantly tell him that it's a bug which will be fixed soon! (I guess so of course)

[brettfo]

As a temporary workaround you could:

1. Disable the nightly F# feed from within VS.
2. Remove the bad F# build from a developer command prompt: VSIXInstaller.exe /uninstall:VisualFSharp.
3. (optional) If you still want newer bits, manually install the last good package from here.

[realvictorprm]

I'm sharing the workaround for those who are facing the issue. Thanks for posting @brettfo

[brettfo]

I've also deleted the bad build from the package source, but you'll still have to manually remove any existing installs and it may take a few minutes for the bad one to actually get unlisted.