Could not start the julia language server in VS Code

Have a look if the 'LanguageServer' package is actually installed/somehow uninstalled, this happened to me. After manually installing it, it was all fine and dandy again.

Indexing all the packages still takes ages, though.

VS Code settings don't seem to always play nice with backslashes. Try instead single slashes, even on Windows:

"julia.executablePath": "c:/Program Files/Julia/Julia-0.5.0/bin/julia.exe"

It may, however, also be a problem with the blank in 'Program Files', in which case the legacy 8.3 filename convention could work:

"julia.executablePath": "c:/PROGRA~1/Julia/Julia-0.5.0/bin/julia.exe"

Note that you would typically have both 'C:\PROGRA~1' and 'C:\PROGRA~2' pointing to 'C:\Program Files' and 'C:\Program Files (x86)', respectively. Find the correct one from the console.

I had the same problem, just run Julia REPL and switch to pkg mode with ] and add LanguageServer package with add LanguageServer and restart vs code.