If after you install SharePoint 2007 you are unable to edit or create content source schedule, your WSS_WPG group does not have correct permissions to the %windir%\Tasks folder on the server designated for indexing service on your MOSS farm. This is the directory where Windows Scheduler stores scheduled tasks.
Following the steps below will resolve this issue:
1. Use an account that has administrative permissions to log on to the computer that is running the Office SharePoint Server 2007 indexing service.
2. Click Start, click Run, type cmd, and then click OK.
3. Type the following command at the prompt, then press Enter attrib –s %windir%\tasks Note: %windir% is the path of the Windows folder.
4. In Windows Explorer, right-click the Tasks folder, and then click Properties.
5. In the Tasks Properties dialog box, click the Security tab, and then click Add
6. In the Select Users, Computers, or Groups dialog box, type WSS_WPG in the Enter object names to select box, and then click OK.
7. Grant the following permissions for the WSS_WPG account, and then click OK:
8. Reset IIS by typing IISRESET at the command prompt.
9. Type attrib +s %windir%\tasks at the command prompt
Following the steps above will eliminate the Access Denied error message, and you should be able to edit or create a content source schedule. We had this issue on one of our MOSS implementations. Although the first thought is that something complex is not working properly with our installation, but the solution is as simple as following the steps above
** About the Author: Anthony Odole is a Senior Solution Architect with IBM Global Services. He is a SharePoint Subject Matter Expert. You can reach him at Odolea@gmail.com