[SalesForce] sfdx’ is not recognized as an internal or external command, operable program or batch file

1.Verify the "Salesforce CLI" installed successfully or not

Go to → C:\Program Files\Salesforce CLI\bin → Verify sfdx.exe should be availble

2.Add this path to environment variables "Path" Go To → Windows Search → Edit environment variables for your account

For now, you need to have the pre-release version installed for DX:

sfdx plugins:install salesforcedx@pre-release

Make sure you've also updated all extensions, including Lightning Web Components, which is not currently part of the Salesforce Extension Pack.

Often, simply restarting after installing/updating all extensions and the pre-release sfdx plugin will automatically create the lwc folder for you. You may also need to close and re-open the folder for it to take effect. I'm not sure how/why my lwc folder appeared, but it wasn't obvious as to what I did.

If all else fails, create a new project in a new, empty directory, and copy the lwc folder back into force-app/main/default/, so that it has two files:

./force-app/main/default/lwc/.eslintrc.json
./force-app/main/default/lwc/jsconfig.json

Once you've done that, you'll stop getting that error and be able to create new components. These config files may require modification if you copy from a new project, so make sure you check the file paths of jsconfig.json. Every time you create a new component with sfdx, jsconfig.json will be updated with more metadata, so make sure you commit this file if you're using a repo.

NOTE: Even though you'll be able to create files locally, to push to the server, you need a pre-release org for now, since all new LWC features are tied to API 45.0 and later, while all production and scratch orgs will be 44.0.