WebCT Backup format
WebCT's course backup format (zip) is a proprietary format used in versions of WebCT up till CE 4.1. It is a zip of several course-related directories, however, zip has been modified so it does not expand as a normal zip file would. It is a snapshot in time of all the files, structure, and student data in a course, so it is currently the only way to fully archive a WebCT site.
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Note: you can generate a tar file of the course-related directories by using this script.
CE Migration Pack (CEMP)
The CE Migration Pack (CEMP) tool was meant to assist institutions to move from CE 4.1.5 to CE 6/Vista 4. CE 6/Vista 4 did not import the course backup zip format that CE4 (and earlier) used.
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Export Confirmed
Entire course has been successfully exported to the folder My-Files in Manage Files. The package filename is COURSEID_COURSE_YYYYMMDDHHMMSS.zip.
Without the CEMP (CE Migration Pack):
The instructions from the Technical Reference guide are:
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you will get a compressed zip.
What's Missing?
This method of export was meant to migrate a CE4 to a CE6/Vista4 site, not an archive. This does not export postings or other student work (e.g., submissions).