Outlook Web Error

Question

Getting this error when attempting to access Outlook web on my MacBook Pro:

Answer 1

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Hi @Quesada, Q (ˈkyü ) 623

Thank you for reaching out. 

As far as I know, the InvalidJson error during StartupData usually indicates that the browser failed to parse a JSON response from Microsoft’s servers. This is often caused by corrupted cache or cookies, network interruptions, browser extensions. 

You could try to to follow these steps to troubleshoot it: 

Test in Private/Incognito Mode 

In Safari: Go to File > New Private Window.

Go to OWA and sign in again.

If the issue does not occur in Private mode, it’s likely related to cached data or extensions. 

Clear cache and cookies (Outlook/Microsoft sites) 

Open Safari > Settings (Preferences) > Privacy > Manage Website Data. Search for: outlook, office, Microsoft, live.com 

Remove the related entries.

Then, enable the Develop menu via Safari > Settings > Advanced > Show Develop menu. 

Go to Develop > Empty Caches. 

Restart Safari and try again. 

Disable Safari Extensions 

Go to Safari > Settings > Extensions.

Turn off all extensions and reload Outlook Web. 

If it works, re-enable extensions one by one to identify the cause (ad blockers or privacy tools are common culprits). 

Please understand that our initial reply may not always immediately resolve the issue. However, with your help and more detailed information, we can work together to find a solution.  

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