What may cause any version of Microsoft Outlook to run slowly?

by Rubin|Published December 6, 2025

I recently experienced a tremendous slowdown while using Microsoft Outlook 2019, but this problem could occur with other versions. This slowdown manifested as a 45 second delay before the app responded to even a single click.

I tried all the forum posted recommendations I could find. The particular post at this URL provides most of what I could find, but none of these solutions worked.