# Troubleshooting

> This page presents the most frequent reasons for which the UiPath Extension for Microsoft Edge might not work properly, and how to solve these issues.

This page presents the most frequent reasons for which the UiPath Extension for Microsoft Edge might not work properly, and how to solve these issues.

## Check if the Extension for Microsoft Edge is installed and enabled

1. In Microsoft Edge, navigate to `edge://extensions/`.
2. Make sure the extension is installed and enabled, as explained [here](extension-for-edge-chromium.md).
3. If the extension was installed correctly but does not appear in Microsoft Edge, check if there are Group Policies that affect the extension, as explained [here](edge-group-policies.md).

![docs image](https://dev-assets.cms.uipath.com/assets/images/studio/studio-359263-4866778f.webp)

## Check if ChromeNativeMessaging.exe is running

The `ChromeNativeMessaging.exe` enables communication between the UiPath Extension for Edge and the UiPath Studio/Robot.

1. Open Microsoft Edge.
2. Open Task Manager.
3. Check if the `ChromeNativeMessaging.exe` process is running.

   ![docs image](https://dev-assets.cms.uipath.com/assets/images/studio/studio-171664-3df5b9f1.webp)
4. If the process is not running:
   * Make sure the extension is installed. For more information on how to install it, check the [docs page](extension-for-edge-chromium.md).
   * Check if there are Group Policies affecting `ChromeNativeMessaging.exe`. See the [docs page](edge-group-policies.md) for more information.
   * Check if the [ComSpec](microsoft-edge-extension-troubleshooting.md#check-if-comspec-variable-is-defined-correctly) environment variable is defined correctly.

## Check if ComSpec variable is defined correctly

### Description

The `ChromeNativeMessaging.exe` process runs under the current user and it uses `cmd.exe` to start the browser.

If the `ComSpec` environment variable is missing or has an invalid value, then Microsoft Edge cannot launch the `ChromeNativeMessaging.exe`.

Furthermore, the administrator may disable the command prompt for some users or configure it to always run with elevated privileges.

### Solution

Manually add the correct value for the `ComSpec` environment variable. This variable is set at Windows installation and must be set to: `%SystemRoot%\system32\cmd.exe`.

![docs image](https://dev-assets.cms.uipath.com/assets/images/studio/studio-170041-a41413eb.webp)

### Other workarounds

If the `ComSpec` environment variable is set correctly but the problem persists, the user may not have permission to run the command prompt. In this case, the `ChromeNativeMessaging.exe` process cannot be started with `cmd.exe` running under the current user.

Starting with [Chromium 120.0.6090+](https://chromiumdash.appspot.com/commits?commit=57c3662e332095c8e7d98255d86e29d3a86c530c&platform=Windows), a [`NativeHostsExecutablesLaunchDirectly`](https://learn.microsoft.com/en-us/deployedge/microsoft-edge-policies#nativehostsexecutableslaunchdirectly) [Group Policy](https://chromium-review.googlesource.com/c/chromium/src/+/4918033) allows admins to turn this on for users in restricted environments (Cloud PCs that forbid `cmd.exe`, for example).

![docs image](https://dev-assets.cms.uipath.com/assets/images/studio/studio-401478-0854e39d.webp)

![docs image](https://dev-assets.cms.uipath.com/assets/images/studio/studio-401482-9ea827ed.webp)

## Enable access to file URLs and InPrivate mode

By default, the extension is not granted access to File URLs or InPrivate mode. To enable these:

1. In Microsoft Edge, navigate to `edge://extensions/`. The Microsoft Edge Extensions page is displayed.
2. Navigate to the **UiPath Browser Automation** extension and click the **Details** button.
3. Make sure the **Allow in InPrivate** and **Allow access to file URLs** options are selected.

   ![docs image](https://dev-assets.cms.uipath.com/assets/images/studio/studio-359259-c18304d1.webp)

## Multiple browser profiles

### Multiple Microsoft Edge instances with multiple user profiles

UiPath Extension for Microsoft Edge does not support automating **multiple browser instances** running with **multiple user profiles** at the same time. Therefore, browser automation requires you to close all active instances of Microsoft Edge and restart the browser using a single user profile.

### Stopping all Microsoft Edge instances

In some cases, Microsoft Edge background processes prevent it from closing completely, which interferes with automations even if the browser instance is not visible.

We recommend closing Microsoft Edge by right-clicking the Microsoft Edge icon in the System Tray, and selecting **Close Microsoft Edge**. This ensures that no other user profiles remain in use in the background.

![docs image](https://dev-assets.cms.uipath.com/assets/images/studio/studio-168853-9d74563c.webp)

## Known Issues Specific to MV3 Extensions

### Click activity with Simulate fails on specific web page elements

The Click activity with the `Simulate` input method no longer works on HTML elements that have a click handler with `javascript:` URI.

![docs image](https://dev-assets.cms.uipath.com/assets/images/studio/studio-168089-f282a6f1.webp)

In this case, the simulated click will not take effect and no errors will reported.

This was reported as a Chromium bug here: https://bugs.chromium.org/p/chromium/issues/detail?id=1299742 This issue is quite rare as very few HTML elements have click handlers in this form.

**Workaround**

Change the input method for the failing Click activity from `Simulate` to any other input method:

* Chromium API
* Hardware Events
* Window Messages

### The DeveloperToolsAvailability Group Policy value must be set to 1

The [DeveloperToolsAvailability](https://docs.microsoft.com/en-us/deployedge/microsoft-edge-policies#developertoolsavailability) has the following possible values:

* 0 = Disallow usage of the Developer Tools on extensions installed by enterprise policy, allow usage of the Developer Tools in other contexts
* 1 = Allow usage of the Developer Tools
* 2 = Disallow usage of the Developer Tools

If the UiPath Extension for Edge is installed using [Group Policy](extension-for-edge-chromium.md#install-from-group-policy), then the [DeveloperToolsAvailability](https://docs.microsoft.com/en-us/deployedge/microsoft-edge-policies#developertoolsavailability) must be set to `1` to enable the full functionality of the extension.

This value is automatically set correctly when the extension is installed but it will be overwritten if your system administrator has set another value for this policy.

The other values for [DeveloperToolsAvailability](https://docs.microsoft.com/en-us/deployedge/microsoft-edge-policies#developertoolsavailability) cause the problems listed below.

If [DeveloperToolsAvailability](https://docs.microsoft.com/en-us/deployedge/microsoft-edge-policies#developertoolsavailability) is set to `0` then:

* The UiPath Extension for Edge will be restricting to working with LTS versions of UiAutomation (19.10.x, 20.10.x, 21.10.x, 22.4.x)
* The `InjectJS` Activity will not work.

If [DeveloperToolsAvailability](https://docs.microsoft.com/en-us/deployedge/microsoft-edge-policies#developertoolsavailability) is set to `2` then:

* All the limitations from `DeveloperToolsAvailability=0` apply
* The `ChromiumAPI` input method will not work.

### The UiPath Web Automation browser window shows a warning

The UiPath Web Automation browser window shows the following warning if `ChromeNativeMessaging.exe` could not be started:

`Cannot communicate with UiPath Platform The native part of the extension is not configured correctly.`

Re-install the extension from UiPath Studio.

![docs image](https://dev-assets.cms.uipath.com/assets/images/studio/studio-170256-4de95b03.webp)

See [Check if ChromeNativeMessaging.exe is running](microsoft-edge-extension-troubleshooting.md#check-if-chromenativemessagingexe-is-running).

### Open Browser activity has an insufficient timeout

For MV3 extensions, the browser loads the extension later, after the web pages have loaded. This means that on slower machines, the **Open Browser** activity from **UiPath.UiAutomation.Activities** version 20.10 or older can reach the internal timeout of 20 seconds before the extension has started.

Starting with **v21.10.8**, you can configure the timeout through the `UIPATH_OPEN_BROWSER_TIMEOUT_SECONDS` environment variable. For example, set `UIPATH_OPEN_BROWSER_TIMEOUT_SECONDS=120` to use 120 seconds for the activity's timeout, instead of the default value of 60 seconds.