We have archived some data in the SAP system which was based on non unicode . If we are upgrading the SAP system to the latest version and convert it to uinicode .
In the upgraded uniode system Is it possible to access/read the archived data based on the old non unicode system ?
If you archive data before you do your Unicode conversion, it will absolutely be readable after the Unicode conversion. It is recommended to do as much data archiving as possible before your Unicode conversion to reduce the amount of system downtime.
Please see the following article by Georg Fischer and Tanja Kaugmann from SAP:
Hope this helps.