Can't restore my backup file (SQLServer 2005)

Hi everyone,
This is how I backup:

  1. From right click menu on “Diary” database I select: “Tasks” and then “Backup”;
  2. At the “Back Up Database - diary” window I select:
    a. “diary” at the “Database” scrolling list;
    b. Radio button “Database” at “Backup component” area;
    c. “Disk” radion button at “Back up to” area and then I press the “Add” button for a location on the disk;
  3. I select the “option” menu item from “Select a page” area and I select: “Back up to the existing media” set and “overwrite all existing backup sets”;
    OK, and I get a message that says: “The backup of database ‘diary’ completed successfully”.
    I try (unseccessfully !) to restore that database as follows:
  4. From right click menu on “Diary” database I select: “Tasks” and then “restore” and “Database”;
  5. In the “Restore Database - diary” window I select “diary” from the “Destination for restore” scrolling list;
  6. I select the “From device” radio button and in the “Specify Backup” window I click “Add” and from its’ location on the disk I select the “diary.bak” file I backuped before;
  7. I select “Options” menu item and I select “Overwrite the existing database” radio button;
  8. in the “Original file name” list I see 2 files:
    a. “diary-------c:\program files\Microsoft SQL Server\MSSQL 3\ MSSQL\DATA\diary.mdf”
    b. “diary-------c:\program files\Microsoft SQL Server\MSSQL 3\ MSSQL\DATA\diary_log.ldf”
  9. For the first item I select the location where I backed up diary.bak on disk (d:\diary\ est.bak) and I leave the second item as is;
    When I press OK I get an error message that says:

restore failed for server 'HOME'. (microsoft.SqlServer.Smo)
Additional information
System.Data.SqlClient.SqlError: The media set has 2 media families but only 1 are provided. All
members must be provided. (Microsoft.SqlServer.Smo)

Any idea why can’t I restore my DB?
Thanks a lot !