[🐛 Bug]: SE_MANAGER_PATH needs to point to the binary

[stefandrissen]

Description

I am trying to use the Selenium Manager, so updated the ancient Selenium version we were using to the latest version.

For some reason in our AZDO build pipeline the Selenium Manager is not found. All dlls (from mstest) are in an out folder, but the selenium-manager.exe is not there.:

Initialization method MyTestInitialize threw exception. System.IO.FileNotFoundException: System.IO.FileNotFoundException: Selenium Manager binary 'selenium-manager.exe' was not found in the following paths:

c:\agent\_work\user_host 2025-10-17 09_46_59\Out\selenium-manager.exe
c:\agent\_work\user_host 2025-10-17 09_46_59\Out\runtimes\win\native\selenium-manager.exe.

It is available in the inital msbuild output folder, so environment variable SE_MANAGER_PATH to the rescue.

I pointed it at the output folder where selenium-manager.exe resides, but still failing. Google was unable to find the exact error message, but I did find it here:

selenium/dotnet/src/webdriver/SeleniumManager.cs

Lines 50 to 56 in 4fa3952

	string? binaryFullPath = Environment.GetEnvironmentVariable("SE_MANAGER_PATH");
	if (binaryFullPath is not null)
	{
	if (!File.Exists(binaryFullPath))
	{
	throw new FileNotFoundException($"Unable to locate provided Selenium Manager binary at '{binaryFullPath}'.");

So SE_MANAGER_PATH is expected to point to the binary, which I did not really expect.

Reproducible Code

//

[selenium-ci]

@stefandrissen, thank you for creating this issue. We will troubleshoot it as soon as we can.

Selenium Triage Team: remember to follow the Triage Guide

[nvborisenko]

@stefandrissen does it work with v4.35?

[stefandrissen]

@nvborisenko I do not know, we updated to v4.36 from an ancient (I think v4.0, but pre v4.6) to be able to use the Selenium Manager.

[nvborisenko]

In the latest v4.36 there issue: #16400, most likely it is already resolved, but not released yet. This is why I ask your help to verify previous v4.35.

[stefandrissen]

I see, unfortuantely I cannot easily get v4.35 into our build pipeline.

Anyway, this issue is more about what the environment variable SE_MANAGER_PATH is expected to point to.

The current code shows that it is looking for the file whereas I expected, and provided, the folder.

Maybe the resolution should be hybrid:

• if it is pointing to a folder, then use that folder + default manager name
• if it is pointing to a file, then just use the file

[nvborisenko]

Understood, thanks for clarification.

https://www.selenium.dev/documentation/selenium_manager/#alternative-architectures

However, as of Selenium 4.13.0, the Selenium bindings allow locating the Selenium Manager binary using an environment variable called SE_MANAGER_PATH. If this variable is set, the bindings will use its value as the Selenium Manager path in the local filesystem. This feature will allow users to provide a custom compilation of Selenium Manager, for instance, if the default binaries (compiled for Windows, Linux, and macOS) are incompatible with a given system (e.g., ARM64 in Linux).

@SeleniumHQ/selenium-tlc needs to decide whether SE_MANAGER_PATH env var can accept both directory or file. My concern is if it is directory then it is still not clear where to find exact custom binary. Providing exact full path to the custom file is straightforward.

[nvborisenko]

@stefandrissen v4.37 is out, can you please verify whether the original issue is resolved, when you didn't provide Se_MANAGER_PATH env var?