Dear Vikas Sharma,
Welcome to the Microsoft Q&A forum.
Thank you for sharing the details of your issue. Based on the information provided, it seems that you are unable to search for emails in the new Outlook after importing your PST file.
To help us understand the situation better, may I ask when you imported the PST file? Depending on the size of the PST, it may take 24–48 hours for all data to finish processing and become fully searchable.
If more than 48 hours have passed and the imported emails still do not appear, please try switching to Outlook Classic or installing it again using the guide from Microsoft Support: Install or reinstall classic Outlook on a Windows PC - Microsoft Support. After that, try importing the PST file once more to check whether the issue continues.
Could you also help check whether you can search for your emails in Outlook on the web?
If search works on the web but not in the new Outlook, please try clearing the local cache by following these steps:
- Press Windows + R to open the Run dialog.
- Enter %localappdata%\Microsoft\Outlook
- Open the RoamCache folder.
- Select all files inside and delete them to manually clear the cache.
If you are using a Mac device, you can follow this method to clear the cache: Clear the cache in Outlook for Mac - Microsoft Support
Lastly, could you let us know the steps you used to export the PST file and whether it was exported from an IMAP account or an Outlook/Microsoft 365 account? This information will help us identify the cause more accurately.
If you need help refining this further or want a more formal version, feel free to ask.
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