So you have a problem with your HP CD-Writer +9100 in not being able to burn brands of CD-Rs that you were able to record previously in the same HP device? You are also unable to read CD's previously recorded in that same Device?
You are able to Read the CD's recorded previously in the HP CD-DVD burnner if you run them in your Hitachi GD2000- DVD-ROM drive?
What type of Registry Repairs you have already done?
If you have made sure that the registry is not corrupted by having entries that the DVD-ROM drive is a Burner and the CD-RW drive is a ROM drive, I suggest you try for a Firmware install for your HP CD-Writer+9100
Take a look at:
HP CD-Writer Plus Drives - Firmware Update Available for the 9100, 9110 and 9200, 9210 Drives
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