Outlook web add-in sideloading: can not delete or add add-ins any more

Question

I could sideload Outlook web add-in by clicking File -> Manage Add-ins, which shows a webpage with a popup, allowing me to add by pointing to my manifest.xml, or to delete what I added there. This worked some days.

Now my Outlook is littered with previously added add-ins. I can not add or remove any more, because when I click File -> Manage Add-ins, that page does not have that popup any more. No other menu on web outlook will reach that popup, including visiting https://outlook.office365.com/owa/?path=/options/manageapps now.

I tried the following to no avail:

• signout at File -> Office Account
• re-add the account in Outlook
• create a new profile in Outlook
• uninstall Office365 and then re-install it
• completely delete browser cache
• trying both chrome and edge browsers
• follow https://learn.microsoft.com/en-us/office/dev/add-ins/testing/clear-cache , that is to delete
• %LOCALAPPDATA%\Microsoft\Office\16.0\Wef\
• %userprofile%\AppData\Local\Packages\Microsoft.Win32WebViewHost_cw5n1h2txyewy\AC#!123\INetCache\
• %userprofile%\AppData\Local\Microsoft\Outlook\HubAppFileCache

I can't download Microsoft Edge DevTools because the download link doesn't work, also not sure if the company pc allows that.

I tried all the above while closing Outlook when applicable.

This is Office 365 on Windows 10 Enterprise.

Anything else I can do?

Thanks,

William

Answer 1

Hi @William

Yes, you don't need to click on any of the options after clicking Manage Add-ins.

Glad to hear this issue has been resolved! Thanks for the sharing.

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[Outlook web add-in sideloading: can not delete or add add-ins any more.]

Issue: I could sideload Outlook web add-in by clicking File -> Manage Add-ins, which shows a webpage with a popup, allowing me to add by pointing to my manifest.xml, or to delete what I added there. This worked some days.

Solution: What happens is due to the highly restrictive corporate network it takes minutes before the popup allowing to add/remove add-in to appear. And if I click anything, or in at least two cases merely move mouse across that page before that popup appears, then it will never appear.So in short, just need to open that page, refrain from clicking anything and not even move mouse on that page, just stare at the page, possibly for minutes, and the popup will eventually appear, allowing to add/remove add-ins.

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Answer 2

I think this is resolved now. What happens is due to the highly restrictive corporate network it takes minutes before the popup allowing to add/remove add-in to appear. And if I click anything, or in at least two cases merely move mouse across that page before that popup appears, then it will never appear.

So in short, just need to open that page, refrain from clicking anything and not even move mouse on that page, just stare at the page, possibly for minutes, and the popup will eventually appear, allowing to add/remove add-ins.