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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 to resolve it?


    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 > Resources > Search Configuration > External Search Resources.

    2. Click: WorldCat.

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


    Additional Information

    1. 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.
    2. 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. 
    3. Note that z39.50 is on port 1921 or 210; be sure these ports are open at your institution
    4. For  general information about configuring external search profiles, please see the Online Help.
    5. 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." More here:
    6. For Network environments - please check configuration of "Placement of new records and template". More in this article, "MD Editor, External Resources: Z39.50 gate error", and the Online Help regarding "External System Search when Using a Network Zone".


    • Article last edited: 5-Feb-2021
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