How to troubleshoot the "Could not create 'CDO.Message'" error message



https://support.microsoft.com/en-us/kb/910360

Method 1: Make sure that the Cdosys.dll file is correctly registered

1. Determine whether the Cdosys.dll file is correctly registered. To do this, follow these steps:
   1. Click Start, click Run, type regedt32, and then click OK.
   2. In Registry Editor, locate and then expand the HKEY_CLASSES_ROOT registry subtree. Expand TypeLib, and then locate {CD000000-8B95-11D1-82DB-00C04FB1625D}.
   3. Expand {CD000000-8B95-11D1-82DB-00C04FB1625D}, expand 1.0, and then click 0.
   4. Click win32, and then confirm that the following value is displayed in the right panel:
      Drive:\WINDOWS\system32\cdosys.dll
2. Register the Cdosys.dll file. To do this, follow these steps:
   1. Click Start, click Run, type regsvr32 %systemroot%\system32\cdosys.dll, and then click OK.
      
      Note You may receive the 0x800704da error code if multiple versions of CDO exist on the same operating system. To resolve this issue, use the regsrv32 -u cdosys.dll command to unregister the Cdosys.dll file. Then, reregister the Cdosys.dll file by running the following command:
      regsvr32 %systemroot%\system32\cdosys.dll
      For more information about CDO versions, visit the following Microsoft Developer Network (MSDN) Web site:
      http://msdn2.microsoft.com/en-us/library/ms978698.aspx

Method 2: Grant permissions for the user account to access the registry key for CDO for Windows 2000 Library

1. Grant permission for the user account to access the registry key for CDO for Windows 2000 Library.
2. Click Start, click Run, type regedt32, and then click OK.
3. In Registry Editor, locate and expand the HKEY_CLASSES_ROOT registry key. Expand TypeLib, and then locate {CD000000-8B95-11D1-82DB-00C04FB1625D}.
4. Right-click {CD000000-8B95-11D1-82DB-00C04FB1625D}, click Permissions, and then click Add.
5. Type ComputerName\UserName, and then click OK
   
   Note The placeholder ComputerName represents the name of the computer. The placeholder UserName represents the name of the user.
6. Click to select the check box in the Allow column to grant Read permission to the user, and then click OK.