Hi Nabil,

There are several third-party software programs that allow you to backup, restore, and manage your Internet browser bookmarks or favorites. However, all modern browsers include bookmark managers capable of backup (export) and restoration (import).
You can follow the below steps to save your favorites first and then format your machine.

Method 1: Internet Explorer versions 5.0 to 8 users backing up favorites.

1. Within Internet Explorer, click the File menu and Import and Export.
2. Within the Import and Export window click Next.
3. Click Export Favorites and click Next.
4. Select the folder you want to backup; if you want to backup all favorites, leave the Favorites folder highlighted and click Next.
5. Select the destination where you want to save your favorites and click Next.
6. Click Finish.

Method 2: Internet Explorer versions 9 and above users backing up favorites.
Step 1: Export the favorites first.

1. Click the Favorites icon in the upper right corner.
2. Click the down arrow next to Add to favorites (or press Alt+Z on your keyboard as a shortcut).
3. Select Import and export in the pop-up menu.
4. In the Import/Export Settings window, select Export to a file and click Next.
5. Check the box for Favorites and click Next.
6. Select the folder of favorites you want to export and click Next.
7. Click the Browse button to select where to save the favorites file on your computer and click OK.
8. Click the Export button to backup the favorites, then click Finish.

Internet Explorer versions 9 and above restoring favorites with a backup file.

1. Click the Favorites icon in the upper right corner.
2. Click the down arrow next to Add to favorites (or press Alt+Z on your keyboard as a shortcut).
3. Select Import and export in the pop-up menu.
4. In the Import/Export Settings window, select Import from a file and click Next.
5. Check the box for Favorites and click Next.
6. Click the Browse button to find and select the backup favorites file on your computer and click OK.
7. Select a favorites folder to import the backup favorites into.
8. Click the Import button to restore the favorites, then click Finish.

Step 2: Then import the favorites back again.
Internet Explorer versions 9 and above restoring favorites with a backup file.

1. Click the Favorites icon in the upper right corner.
2. Click the down arrow next to Add to favorites (or press Alt+Z on your keyboard as a shortcut).
3. Select Import and export in the pop-up menu.
4. In the Import/Export Settings window, select Import from a file and click Next.
5. Check the box for Favorites and click Next.
6. Click the Browse button to find and select the backup favorites file on your computer and click OK.
7. Select a favorites folder to import the backup favorites into.
8. Click the Import button to restore the favorites, then click Finish.

Method 3: Internet Explorer versions 9 and above importing favorites from another browser.

1. Click the Favorites icon in the upper right corner.
2. Click the down arrow next to Add to favorites (or press Alt+Z on your keyboard as a shortcut).
3. Select Import and export in the pop-up menu.
4. In the Import/Export Settings window, select Import from another browser and click Next.
5. Check the box for the browser of where you are importing your favorites.
6. Click the Import button to import the favorites, then click Finish.

I hope this helps in keeping your favorites safe and then format your machine.

Regards,
Lokesh