Launching from cmd opens multiple Kantu windows


Launching Chrome and Kantu from a .vbs script, passing arguments to the HMTL file produced by testsuites, can lead to multiple Kantu windows opening.

The number of windows is random and so not reproducible: a couple of days ago 4 opened; today 3; last week 2.

The script worked, although the other day it failed several times, making it hard to rule out a cause.

[Recreator required] Run macro via bookmarks open multiple kantu windows
Tab Open sometimes open multiple tabs without reason

This sounds like some kind of timing issue inside the Kantu launch code. We will try to recreate this.

…although the other day it failed several times,

As a workaround, you can check the macro status and relaunch Kantu if needed. For example script code, please see the run a macro “forever” powershell script.


I considered your suggested workaround yesterday but I’m not sure it’s the optimal solution for my use-case (I’m reading from a csv file and writing to another).

Anyway, if it helps further debugging, some more info…

When the Kantu window opens, multiple messages appear, saying:

“can only run testsuites when it’s not recording or playing”

There must be around 10 of these messages which eventually disappear.

Another issue that may be related (or not - in which case I’m happy to open another post):

My Kantu script opens each URL in a new tab, where it does its business before closing it, and so on.

Sometimes, multiple tabs open with the same page, slowing the script somewhat. At its worst, I’ve seen 8 tabs.

Hope this helps


Hi @admin @TechSupport

This bug is caused from the command

selectWindow | TAB=OPEN |

When it will be solved because it happens that it also opens a large number of tabs in a random way.



Hi @admin @TechSupport

To help you to find and fix this bug i add my code.

Today I create this simple macro and run it more times.

  "Name": "_test_open",
  "CreationDate": "2019-4-11",
  "Commands": [
      "Command": "bringBrowserToForeground",
      "Target": "",
      "Value": ""
      "Command": "selectWindow",
      "Target": "TAB=OPEN",
      "Value": ""

First time the macro open 1 tab (correct), after i closed firefox, and reopen firefox after some minutes, I run the same macro and this time opend 4 tabs with the same url (wrong).

I never used loop or others commands.

Sometimes give to the error “Error #101: Kantu is not connected to a browser tab”

I use firefox 66 with Windows 7 and Xmodules free installed.

I hope you can quickly correct these errors that make automation difficult…

Thanks, have a nice day