Lost all my outlook contacts

 Losing your contacts in Outlook can be a frustrating experience, but there are a few steps you can take to try and recover them. Here's what you can do:

1.  Check for Updates: Ensure you are using the latest version of Outlook and that it's up to date. Sometimes, updating the software can resolve synchronisation and data loss issues.

2.  Check the Outlook Address Book Service:

a. Open Outlook and go to the "File" tab.

b. Click on "Account Settings" and then "Account Settings" again.

c. Go to the "Address Books" tab and make sure your Contacts folder is marked as an Outlook Address Book.

d. If the Outlook Address Book Service is not added , click on "New" or "Add" and choose "Outlook Address Book" to add it.

e. Close and restart Outlook for the changes to take effect.

3.  Recover Deleted Contacts: If you've permanently deleted your contacts, they might still be recoverable. Outlook often retains deleted items for a certain period. Here's how to attempt recovery:
a. Open Outlook.

b. Click on "Deleted Items" or "Recover Deleted Items" (this may vary depending on your version of Outlook).

c. Look for your contacts and select them.

d. Click "Recover" to restore them to the default location.

4.  Check Other Folders: It's possible that your contacts have been moved to another folder. Look in the "Other Contacts" folder or in other folders where you might have accidentally moved them.

5.  Search for Contacts: Use the search function in Outlook to look for your contacts by name or email address. Sometimes, they may still be in your Outlook database but not in the Contacts folder.

6.  Check Data File: In some cases, your Outlook data file (PST file) may have become corrupted. You can run the built-in "Inbox Repair Tool" (scanpst.exe) to fix issues with your data file.

7. Recover from a Backup: If you have a backup of your Outlook data, you can restore your contacts from the backup. You may have backed up your data to an external hard drive, cloud service, or a previous PST file.

8. Sign out and Sign in Again. Try clearing the cache and see if you will get your contacts back."

Answer taken from https://learn.microsoft.com