You cannot install OS 5.00 over anything on your laptop. If you want to keep programs from your NR70, go to folder C:\Program Files\Sony Handheld\Yoursurname\Backup, where C:\ is the name of the drive where you have installed your NR70 Clié desktop and Yoursurname is a user name you used in your NR70. Copy whole Backup folder but do not forget to delete any hacks from it first. Then you can safely unistall your old Clié desktop (you will not need it anymore, as a repair of your NR 70 is not worth of money - unfortunately...). Install new desktop and drivers for your new NZ 90 and syncronize for a first time. Go again to the same directory (C:\Program Files\Sony Handheld\Yoursurname\Backup), which has been created automaticaly and paste all files (except hacks) there. Syncronize again. If some programs on your new NZ 90 will not work, they are probably not compatible, you have to delete them
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