CoD4: MW does not start in Singleplayer mode.

I recently purchased CoD4: MW.  Despite numerous attempts, I can not get the game to start in Singleplayer mode.  If I launch the game by inserting the DVD or by manually initiating AutoPlay from the DVD-ROM disk icon in My Computer, I get the Call of Duty 4: Modern Warfare Activision/Infinity Ward splash screen followed by the Main Menu page.  After selecting "Play Singleplayer", the Main Menu page closes, the computer reads the DVD-ROM and I get an Error Message dialogue box that says "Cannot locate the DVD-ROM.  Please insert the correct DVD-ROM, select and restart application".  If I attempt to start Singleplayer mode from either the Start Menu shortcut or the Desktop shortcut, the computer reads the DVD-ROM and I get the same Error Message dialogue box.

I have the same problem regardless of what patch is installed.  I tried to start Singleplayer mode with the game unpatched and with the 1.4, 1.6 and 1.7 patches installed with the same results.

If I start the game in Multiplayer mode, whether I automatically or manually AutoPlay the DVD-ROM or select Multiplayer from the Start Menu or Desktop Shortcuts, everything works fine.  I can get online, join a server and play the game.  The problem is with Singleplayer mode.  I want to play in Singleplayer mode for a while to get a feel for the game before I go online.

Last week, there was a thread in the old forums that listed troubleshooting ideas for resolving problems with the game.  The old forums and that thread are unaccessible since the change over to the new forum.  Can someone please find that old thread and repost it/sticky it here in the new forums?

Thanks in advance