In essence, CD-ROMs are not inherently susceptible to Y2K problems. For CDs with textual data this is what is important. CD-ROMs with databases are more complicated. Those users who extract databases from the CDs and import them into other programs will experience the most serious ramification of two-digit year fields. Even in this case, however, it is a simple matter in major database and spreadsheet programs to change two-digit dates to four digits with a global command.
Some programs also convert the underlying data fields.
In addition, one agency, the U.S. Patent and Trademark Office, has certified that its current CDs are compliant. They advise discarding older CDs, with the exception of archival products such as USAPat and USAMark. Libraries must be careful in discarding, however, because of the depository retention and superseded requirements for depository material. Personal Librarian is now owned by America Online, which has stopped supporting it. America Online has stated that Personal Librarian will NOT be tested for Y2K compliance.