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    Z39.50 gate error for OCLC WorldCat external search, or AMICUS, in Alma

    • Product: Alma



    Searches in WorldCat or AMICUS (through Resources > Search External Resources) result in the message:  "An error has occurred, please try again later and contact the system administrator." (Z39.50 gate error: Connection rejected by the Z39.50 database server.)"

    How can we resolve this?


    OCLC WorldCat requires userId and password.  If connection has worked before, please check that the current password is entered in Alma as well.

    The steps are: 

    1.Go to Configuration > Resource Management > External Search Resources.

    2. Click: WorldCat.

    3. In the "Credentials" field, type the userId and password, using this format: userId/password. For example, if the userId is walt and the password is whitman, enter: walt/whitman


    Additional Information

    Some customers find that simply re-typing the known credentials solved the connection error. In some cases, deleting and re-adding the WorldCat configuration in Configuration > Resource Management > External Search Resources resolved the error.

    Note that for WorldCat, the OCLC Connexion userid/password should have full cataloging privileges. Customers have reported that it is not possible to use a Catexpress ID or FirstSearch login. 

    For more general information about configuring external search profiles, please see the Online Help.


    Relevant information from OCLC is available here:

    "ID Authentication - OCLC supports ID/authentication as prescribed by the standard. We recognize the userId and password fields; the groupId field is ignored. The service patron password is the password that must be used."


    • Article last edited: 29-Aug-2018