CD-ROMs are very resilient and sturdy. Unless there is a major crack or you 
played frisbee with your dog, (smile) your VTB CD-ROM is not defective. If it 
was, you would not be able to read anything at all from the CD-ROM. Nowadays,
we all have big hard drives so space limitation should not be an issue.

Please try copying the contents of the CD-ROM (root and Installation 
directories) to a directory on your hard disk. (You can always delete 
them afterwards to recover the wasted space). 

Then execute the Setup program from the hard disk instead of your CD-ROM
Drive. If the files were copied without errors and the Software was installed
successfully, you may be certain that your VTB CD-ROM is fully functional but
there may be an issue with the CD-ROM Drive instead - that you may wish to 
address - which is overcome when you run the Install from the Hard Drive.
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