The Assignment tool in Blackboard contains an Item Download feature, which allows instructors to download all student submissions to your computer in a ZIP file.
AssignmentItemDownloadError
In some cases, the error message is caused by a faulty file submitted by the student. Please check to see that none of the file names contain odd characters such as %. If so, resetting the assignment and asking the student to resubmit the assignment may clear up the error message.
In other cases, there is a possibility that there is an issue with this feature which is converting spaces in Assignment titles to plus (+) signs in the ZIP filename (example: Draft+1+Essay.zip). Blackboard cannot parse special characters like plus signs, so attempting to download the ZIP file will result in an error.
As of February 17, 2009, we are still looking into the problem. Until then, here is a workaround:
Rename your assignment to remove the space:
1. In the Control Panel, go to the Content Area where your assignment is located.
2. Click the Modify button to the right of the assignment.
3. Remove the space from the assignment Name and click Submit.
4. Follow the Item Download instructions.
For more details on this bug, check out TLT Blackboard Support Blog (although note that the first workaround listed does not work for our server).
Posted by chabotbbteaching 