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Power Platform Community / Forums / Power Automate / Failed to assume contr...
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Failed to assume control of Firefox

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Posted on by 37

Hello,

 

Since a couple of weeks, I get systematically the error in the title of this topic. The flow works perfectly. I haven't changed the code, so it wasn't suppose to dysfunction. I suspect an extra PAD problem. I tried various solutions :

 

- Reinstall the Microsoft Power Automate extension and try again. Same error.

- Try to install the extension to edge and chrome (with private navigation too). Same error.

- Control if "ComSpec" system variable exists, and it's the case.

- Reinstall PAD. Same problem.

 

Here are the screens for more information :

 

Magic_0-1666634537477.png

 

Magic_1-1666634540370.png

 

logs :

 

 

Microsoft.Flow.RPA.Desktop.Modules.SDK.ActionException: Impossible d’assurer le contrôle de Firefox (la communication avec le navigateur a échoué. Essayer de recharger l’extension). ---> Microsoft.Flow.RPA.Desktop.UIAutomation.WebAutomation.Core.Browser.WebBrowserException: Une exception de type 'Microsoft.Flow.RPA.Desktop.UIAutomation.WebAutomation.Core.Browser.WebBrowserException' a été levée.
 à Microsoft.Flow.RPA.Desktop.UIAutomation.WebAutomation.Core.WebExtensionsBrowser.WebExtensionsBrowserLauncher.LaunchNew(ProcessWindowStyle processWindowStyle, String initialUrl, Int32 timeout, WebPageCourseOfActionIfDialogAppearsEnum dialogHandlingMode, String dialogButtonName)
 à Microsoft.Flow.RPA.Desktop.UIAutomation.Plugin.Firefox.Firefox.StartNew(ProcessWindowStyle processWindowStyle, String initialUrl, Int32 timeout, WebPageCourseOfActionIfDialogAppearsEnum dialogHandlingMode, String dialogButtonName)
 à Microsoft.Flow.RPA.Desktop.Modules.WebAutomation.Actions.WebAutomationActions.LaunchNewFirefox(String initialUrl, String firefoxTabTitle, String firefoxTabUrl, String dialogButtonToPress, Int32 operation, Int32 windowState, Int32 attachMode, Boolean waitForWebPageToLoad, Int32 waitForPageToLoadTimeout, Int32 courseOfActionIfDialogAppears, Boolean clearCache, Boolean clearCookies, Int32 timeout)
 à Microsoft.Flow.RPA.Desktop.Modules.WebAutomation.Actions.LaunchFirefoxBase.Execute(ActionContext context)
 --- Fin de la trace de la pile d'exception interne ---
 à Microsoft.Flow.RPA.Desktop.Modules.WebAutomation.Actions.LaunchFirefoxBase.Execute(ActionContext context)
 à Microsoft.Flow.RPA.Desktop.Robin.Engine.Execution.ActionRunner.Run(IActionStatement statement, Dictionary`2 inputArguments, Dictionary`2 outputArguments)

 

 

Did you have any suggestion to solve this problem ?.

 

Best regards.

  • VJR Profile Picture
    7,635 on at

    The Firefox add-on was unavailable for a while but is back now.

    So would recommend to install it as per the latest product update instructions mentioned a few days ago.

    https://powerautomate.microsoft.com/en-us/blog/power-automate-for-desktop-mozilla-firefox-web-extension-installation-update/

     

  • Magic Profile Picture
    37 on at

    Okay i'll try it, but it doesn't explain why it doesn't work on chrome and edge too.

  • Verified answer
    Magic Profile Picture
    37 on at

    I can't explain it, but I had opened PAD and I had an error that oblige me to reconnect to my account. And then I was able to launch my flow without any error. Has I expected, I didn't reinstall the PAD extension. Connect and disconnect solved my problem.

     

    This topic is solved.

  • Zygmunt Profile Picture
    39 on at

    I depend on an flow to support a charity in the Amazon. WE are completely stuck, Flow which has been working for many months unchanged and for a year before that fails to assume control of Firefox, Edge and Chrome.  Test snippet newly created fails in similar way.  Made mistake of removing PAD extension from Firefox as I thought this was the problem, now cannot reinstall as cannot locate working link to download, all those kindly suggested above do not work. Link in title of support page dumps you in Bing to read about Harry and Megan. 

  • Magic Profile Picture
    37 on at

    Hello,

     

    For information, the problem newly reappears and i don't know who to resolve it.

  • VJR Profile Picture
    7,635 on at

    @Zygmunt , a member here has attached a physical copy of the addon. Please check if it helps.

    https://powerusers.microsoft.com/t5/Power-Automate-Desktop/Firefox-addon-not-available/m-p/1872777/highlight/true#M20129

     

  • Magic Profile Picture
    37 on at

    Hello @VJR,

     

    I tried it, and it doesn't work for me. It catches the same error. Same error with edge (I uninstall and reinstall the extension)... It looks like they are something weird in the communication between PAD and the extension...

     

    If somebody had the solution...

  • Zygmunt Profile Picture
    39 on at

    I have been trying various work arounds, can't find any that work.  I have tried creating and existing browser (outside PAD) and attaching to the instance but that seems to fail as well (All  browsers). So it would seem that all browser communication is broken rather than the launch.  I can launch a browser and it launched with the correct screen but after that cannot communicate with the browser. 

    I now have a test rig so should know when they fix it, I guess I can set it to run daily to let us all know.

    For me this is extremely urgent as we have lost our main business information feed.  The process has no viable manual alternative.

  • tjones0213 Profile Picture
    41 on at

    I used a workaround documented in Power Automate can't take control of the web brows... - Power Platform Community (microsoft.com) that just worked for me.  I opened Edge, disabled, enabled the latest PAD extension, then refreshed the browser and left it open.  My flow opened a new Edge instance and worked this time

  • Zygmunt Profile Picture
    39 on at

    Sadly did not work for me

    Just going to test with edge alone, my initial test loops through all the browser, then I tried Firefox on it own all failing

    Firefox 108.0.1

    PAD 2.27.00186.22340

    Pad extension 2.0.12 (does anyone know if this is the correct extension for PAD 2.27?)

    thanks for all the help

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