System.IO.IOException: The process cannot access the file 'C:\Users\eric\AppData\Local\NCrunch\MSBuildConfigVS2017.config' because it is being used by another process.
at System.IO.__Error.WinIOError(Int32 errorCode, String maybeFullPath)
at System.IO.FileStream.Init(String path, FileMode mode, FileAccess access, Int32 rights, Boolean useRights, FileShare share, Int32 bufferSize, FileOptions options, SECURITY_ATTRIBUTES secAttrs, String msgPath, Boolean bFromProxy, Boolean useLongPath, Boolean checkHost)
at System.IO.FileStream..ctor(String path, FileMode mode, FileAccess access, FileShare share)
at nCrunch.Common.IO.FilePath..()
at nCrunch.Compiler.GeneratedConfigFileResolver..ctor(String configFileContent, VisualStudioVersion vsVersion)

any suggestions?

this is a new install of 3.1 in the latest VS2017 RC

Hi, thanks for sharing this issue.

There is a fix for this problem coming in v3.2 out later this week.

It should be possible to alleviate the problem by avoiding use of more than one instance of VS2017 at any one time.

I donno if this is related but I have a single instance of VS 2015 open and i get:

The setting '' was not loaded from the NCrunch configuration file at 'C:\Users\phill\AppData\Roaming\NCrunch\globalconfig.crunch.v3.xml' because this setting has been declared in a scope where it is not applicable. Due to limitations in the engine, not all settings can be applied at all levels in the configuration system. If you are attempting to define this setting manually in XML, please inspect the configuration UI to see where it can be applied.

Its a clean install

I think when I uninstalled V2, it left "globalconfig.crunch.xml", so what i did was close VS, removed globalconfig.crunch.xml and globalconfig.crunch.v3.xml, then restarted VS, it did the setup again and this time I'm not getting the error.

So it may just be a conflict between the two. Do you want me to email you the two global files so you can check them to see if there's a patch that's require incase others fall into the same issue?

Thanks for sending through these files. With them, I've managed to reproduce this problem. A fix is pending in the v3.2 release due later this week.

For reasons I can't really explain (but probably have much to do with the faulty wiring in my head), when NCrunch ported settings over from the old v2 config files, it erroneously transferred the global HiddenWarnings from the Tests Window into the 'HiddenComponentWarnings' setting in the new global config. Because 'HiddenComponentWarnings' is only applicable in project settings files, this caused the engine to later kick up an error letting you know something wasn't right.

The global hidden warnings were also being transferred into the settings file into a correct setting, however, so everything would have continued to function as normal. The error is just noise.