AWS SAM fails on Windows 11 Home while trying to create an AWS Serverless project in PyCharm with AWS Toolkit

PyCharm shows an exception like this: 

java.lang.RuntimeException: Could not execute `sam init`!: [Cloning from https://github.com/aws/aws-sam-cli-app-templates (process may take a moment), Error: Unstable state when updating repo. Check that you have permissions to create/delete files in C:\Users\user\AppData\Roaming\AWS SAM directory or file an issue at https://github.com/aws/aws-sam-cli/issues] at software.aws.toolkits.jetbrains.services.lambda.wizard.SamInitRunner.execute$lambda-1(SamInitRunner.kt:55) 

This happens because the PATH variable on Windows 11 is limited to 260 chars (no idea why).

The fix is easy: Open Registry Editor (type "regedit" in Windows Search box)

and go to HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\FileSystem

then change the value for "LongPathsEnabled" from 0 to 1.

You need a Docker on your computer to run a Local SAM build. Install it and run Docker Desktop at least once to accept T&C's and to start the docker service.

Unfortunately, the latest v4.12.0 Docker for Windows  (as of 2022-09-27) does not work well with the latest AWS SAM 1.57.0. 

AWS SAM "Local" build throughs an error. Downgrading to Docker 4.11.1 solves this issue as discussed here.

Python 3.9 is the latest version currently supported by AWS Lambda. Assuming this is what you have selected for your AWS Lambda project, you need to make sure that SAM can find in your path python 3.9 executable' folder. SAM refuses to continue if it knows the path to e.g. python 3.10 but not to python 3.9.