AWS CLI installation failure: Error: Could not verify installed CLIs

## Problem

When trying to install and use Local Stack toolkit for VSCode I encounter an error in the step involving the download of AWS CLI.

When I click install AWS cli through the ‘walkthrough of application builder’ I first get the message

AWS Toolkit could not find AWS CLI. Install a local copy?

I am given two options install and install manually……

I choose install then I wizard pops up I follow the instruction till the end and it ‘appears’ to have successfully installed as I click final finish button in the wizard. However, after the wizard closes I get the following following log error in VSCode:

`2025-09-03 16:33:27.026 [info] Command: (not started) [aws.exe --version]
2025-09-03 16:33:27.044 [info] Command: (not started) [C:\Program Files\Amazon\AWSCLIV2\bin\aws.exe --version]
2025-09-03 16:33:27.060 [info] Command: (not started) [C:\Program Files (x86)\Amazon\AWSCLIV2\bin\aws.exe --version]
2025-09-03 16:33:27.075 [info] Command: (not started) [c:\Users\o\AppData\Roaming\Code\User\globalStorage\amazonwebservices.aws-toolkit-vscode\tools\Amazon\aws.exe --version]
2025-09-03 16:33:27.090 [info] Command: (not started) [c:\Users\o\AppData\Roaming\Code\User\globalStorage\amazonwebservices.aws-toolkit-vscode\tools\Amazon\C:\Program Files\Amazon\AWSCLIV2\bin\aws.exe --version]
2025-09-03 16:33:27.105 [info] Command: (not started) [c:\Users\o\AppData\Roaming\Code\User\globalStorage\amazonwebservices.aws-toolkit-vscode\tools\Amazon\C:\Program Files (x86)\Amazon\AWSCLIV2\bin\aws.exe --version]
2025-09-03 16:33:28.330 [info] Downloading installer from https://awscli.amazonaws.com/AWSCLIV2.msi...
2025-09-03 16:33:35.179 [info] Installing aws-cli from C:\Users\o\AppData\Local\Temp\aws-toolkit-vscode\vsctkb9acb5d3\AWSCLIV2.msi...
2025-09-03 16:33:35.179 [info] Command: (not started) [C:\Users\o\AppData\Local\Temp\aws-toolkit-vscode\vsctkb9acb5d3\AWSCLIV2.msi ]
2025-09-03 16:33:37.575 [warning] childProcess: Process 29364 exceeded memory threshold: 21932.00 MB
2025-09-03 16:34:20.097 [info] Command: (not started) [aws.exe --version]
2025-09-03 16:34:20.116 [info] Command: (not started) [C:\Program Files\Amazon\AWSCLIV2\bin\aws.exe --version]
2025-09-03 16:34:20.133 [info] Command: (not started) [C:\Program Files (x86)\Amazon\AWSCLIV2\bin\aws.exe --version]
2025-09-03 16:34:20.148 [info] Command: (not started) [c:\Users\o\AppData\Roaming\Code\User\globalStorage\amazonwebservices.aws-toolkit-vscode\tools\Amazon\aws.exe --version]
2025-09-03 16:34:20.165 [info] Command: (not started) [c:\Users\o\AppData\Roaming\Code\User\globalStorage\amazonwebservices.aws-toolkit-vscode\tools\Amazon\C:\Program Files\Amazon\AWSCLIV2\bin\aws.exe --version]
2025-09-03 16:34:20.181 [info] Command: (not started) [c:\Users\o\AppData\Roaming\Code\User\globalStorage\amazonwebservices.aws-toolkit-vscode\tools\Amazon\C:\Program Files (x86)\Amazon\AWSCLIV2\bin\aws.exe --version]
2025-09-03 16:34:20.215 [info] Command: (not started) [aws.exe --version]
2025-09-03 16:34:20.235 [info] Command: (not started) [C:\Program Files\Amazon\AWSCLIV2\bin\aws.exe --version]
2025-09-03 16:34:20.251 [info] Command: (not started) [C:\Program Files (x86)\Amazon\AWSCLIV2\bin\aws.exe --version]
2025-09-03 16:34:20.266 [info] Cleaning up installer...
2025-09-03 16:34:20.266 [info] aws-cli installation: Failed
2025-09-03 16:34:20.266 [error] aws.toolkit.installAWSCLI: Error: Could not verify installed CLIs
2025-09-03 16:34:20.267 [info] Removed installer.
`

What is interesting is that after try again and repeating the installation by following the same process and re-clicking then the wizard pops up again and provides me with 3 options. to repair, to remove or to reset which indicated to me that it has been successfully installed by VSCode but it cannot find it or access it.

## Steps to reproduce the issue

1. Open the AWS view in VS Code, navigate to the Application Builder, and select the "Walkthrough" option.
2. In the Walkthrough, you will see many options, click on the first which says 'Install AWS CLI'
3. If it is not installed, then you will be provided 2 options install and install manually. Choose install.
4. From this point the error occurs as described above.

## Expected behavior

The expected behaviour after choosing install is for the AWS CLI to successfully install with no error in the log. The log would normally display a message stating installing successful.

## System details (run `AWS: About` and/or `Amazon Q: About`)

- OS: Windows x64
- Visual Studio Code version: 1.104.0
- AWS Toolkit version: 3.73.0-g376a19b
- Amazon Q version:

Start in the AWS view's Application Builder Walkthrough and trace the Install AWS CLI flow, especially the Windows command checks shown in the report. Reproduce on Windows x64 with the listed VS Code and Toolkit versions, then verify that the installed CLI is found and the walkthrough reports success without “Could not verify installed CLIs”.

Written by the indexing model from the issue text.