"Invalid field data type." when converting to prior version of MS Access.

I'm developing a website that uses a MS Access database. I'm creating the database in Access 2000, but the web server can only open Access 97 databases. I've been using the "Convert Database -> To prior Access Version" for the web server to use, and it's been working fine.

I just added a new table to the database containing the following fields:

ID - AutoNumber, Long Integer, Autoincrement, Primary Key, Not required, Indexed (No duplicates)
paragragh - Memo, Not required, Zero length allowed, Unicode Compression
picture - Text, Max 50, Not required, Zero length allowed, Not indexed, Unicode Compression
picturealignment - Text, Max 5, Not required, Zero length allowed, Not indexed, Unicode Compression
fonttags - Text, Max 100, Not required, Zero length allowed, Not indexed, Unicode Compression

Now when I try to convert it to an Access 97 database I get a

"Invalid field data type."

first, followed by

"Some errors happened during the conversion. No converted database is generated."

Can anyone help me?