Upgrades Plugin fails with the latest Hardhat ("contractFactory.attach is not a function")

I am trying to deploy the OpenZeppelin Upgrades as described in several tutorials, including your own (https://docs.openzeppelin.com/upgrades-plugins/1.x/hardhat-upgrades):

// scripts/create-box.js
const { ethers, upgrades } = require("hardhat");

async function main() {
  const Box = await ethers.getContractFactory("Box");
  const box = await upgrades.deployProxy(Box, [42]);
  await box.waitForDeployment();
  console.log("Box deployed to:", await box.getAddress());
}

main();

and receive the following message:

hardhat run scripts/1.deploy_box.ts

Compiled 1 Solidity file successfully (evm target: paris).
D:\Code\Proxies\solproxy\node_modules@openzeppelin\hardhat-upgrades\src\utils\ethers.ts:7
return contractFactory.attach(address) as Contract; // Needed because ethers attach returns a BaseContract.
^
TypeError: contractFactory.attach is not a function
at attach (D:\Code\Proxies\solproxy\node_modules@openzeppelin\hardhat-upgrades\src\utils\ethers.ts:7:26)
at getContractInstance (D:\Code\Proxies\solproxy\node_modules@openzeppelin\hardhat-upgrades\src\utils\contract-instance.ts:28:26)
at Proxy.deployProxy (D:\Code\Proxies\solproxy\node_modules@openzeppelin\hardhat-upgrades\src\deploy-proxy.ts:87:31)
at async main (D:\Code\Proxies\solproxy\scripts\1.deploy_box.ts:5:15)

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Can anybody point out a working example/tutorial, which would compile and deploy with the latest libraries and tools?

Can you check whether you are using the latest version of the ethers (should be version 6.x) and @nomicfoundation/hardhat-ethers packages?

You can get a sample project by going to https://wizard.openzeppelin.com/, enabling Upgradeability, then Download -> Development Package (Hardhat), then follow the steps in the downloaded package's readme.