To create a portable file, choose File → Create Copy. When QuickBooks displays the first Save Copy or Backup dialog box, select the Portable Company File option button, click Next, and then follow the onscreen instructions. The process, by the way, resembles the backup process.
It’s really easy to save the file on the desktop. Then you can attach it easily to your email and send it out. After the other party receives the file, you can just drag your copy to the Recycle Bin. Your real file remains intact. (A portable file typically must be 10MB or smaller for transmission through most email services.)
To open a portable file, a person (this could be your accountant, your sister in Portland, or me) should choose File → Open or Restore Company. When QuickBooks displays the Open or Restore Company dialog box, this other person just specifies the file that she wants to open as a portable file and then follows the onscreen instructions.