Try the following:
- Change the Sync Slider
- Go to File > Account Settings > Account Settings.
- Select your email account and click Change.
- Look for the Download email for the past: slider.
- Drag the slider to the right to All.
- Click Next > Done, then restart Outlook to allow it to download the older data.
- Use "Search Tools" for Server-Side Results
If you don't want to download everything, you should be able to initiate the server-side search directly:
- Click into the Search box at the top of your Calendar.
- Scroll to the bottom of your initial results and click "More" or "Include older results" if the prompt appears.
- Alternatively, use Advanced Find (Ctrl + Shift + F) to specify a custom date range for your search.
If the above response helps answer your question, remember to "Accept Answer" so that others in the community facing similar issues can easily find the solution. Your contribution is highly appreciated.
hth
Marcin