coldfusion 11 MS access with Unicode

I have coldfusion 11 running on windows 2003 server 32bits and I get today such error when trying to access datasource MS Access with Unicode :

Connection verification failed for data source: clicalbum

com.inzoom.adojni.ComException: Erreur non spécifiée

The root cause was that: com.inzoom.adojni.ComException: Erreur non spécifiée in Microsoft JET Database Engine code=0 Type=1

This error has appeared suddenly. It was working fine yesterday.

I guess something has changed somewhere on the server : where should I look at ?

Thanks for your help

Pierre.