Outlook LaunchEvent never called only for some clients

[thomasdarde]

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We have an addin in charge of updating email signatures deployed on thousands of computers.
It's working as expected for msot clients.

With a specific client the taspane par of the Addin is working perfectly, but LaunchEvent function are never called.
They are on a recent Outlook version (2410) and with a valid MS376 license

What could be the setting/debugging process in this case ?

Your Environment

• Platform [PC desktop, Mac, iOS, Office on the web]: Outlook PC Classic and New
• Host [Excel, Word, PowerPoint, etc.]: Outlook
• Office version number: 2410 (classic) and 1.2024.1124.100 (web)
• Operating System: Windows 11 23h2
• Browser (if using Office on the web): Not relevant

Expected behavior

Our addin should be called when writing an email

Current behavior

Our addin is never called via LaunchEvent, debugging is not easy because it's only happening in production for a specific client (with hundreds of account though)

But we were able to launch Outlook new with devtools , and no relevant message is shown in the console.

It's not a firewall issue (taskpane is using the exact same urls)

I would love to give you more informations but there is nothing I can start with (no log or anything , it's like the addin was not installed)

Steps to reproduce

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Link to live example(s)

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Context

Useful logs

• Console errors
• Screenshots
• Test file (if only happens on a particular file)

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[sivachandran-msft]

HI @thomasdarde , Thanks for reporting it. Could you please share the following details:

• Are you observing this in outlook web?
• Could you please share HAR files & console logs following this procedure https://github.com/OfficeDev/office-js/wiki/Collecting-log-files-for-Outlook-Add%E2%80%90ins-issues
• Do you have any specific scenario this launch events are not working or is it not loading for any of the scenarios?