Hello,
Thank you for posting in Q&A forum.
When you have updated the company details of a user in Active Directory (AD) but the email signature in Outlook still shows the old information, this is usually because the Outlook client has cached the previous signature settings.
To resolve this issue, first make sure the Outlook application is closed on your computer before you can delete the cache. Save any work you may be doing and then exit the application.
Press the Windows + R keys together to open the Run box. Type the following path in the box and press Enter.
%localappdata%\Microsoft\Outlook
It will open a folder containing Outlook profiles and cache files. You want to find the folder that says RoamCache and double-click it to open it.
All the files you currently see on the screen are Outlook cache files. To delete these files, select them by pressing Ctrl + A on your keyboard, right-click on any one of the files and then select the Delete option.
For detailed steps, refer to the following link: How to Clear the Outlook Cache (lifewire.com)
I hope the information above is helpful.
Best Regards,
Yanhong Liu
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