Try this. Go back to your old computer and export your Inbox again. I'm looking at Outlook 2003 here, so I'm assuming your version is quite similar. To export, go to File, Import and Export, select Export to a file, click Next, select Personal Folder File (.pst), click Next, select Inbox, check the box at the bottom of that panel for Include subfolders, and proceed. Then, import that file into the new computer.