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PKIX errors are typically related to certificates that are used when authenticating with an endpoint. This issue happens when your local computer or server attempts to connect to the cloud/internet and the security certificates in your local computer keystore do not match the certificate(provider) of the website. You will have to add the certificate of the website to a local client keystore file "client.truststore". The following steps guide you in making such a local "client.truststore" file from the website that you use to import data from.
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See also WIKI page: ClientConfig XML File for Operator Client and Forecasting Shell Servers - 2021.02 and later#truststore
Once the client.trsutstore truststore file is created, restart your Delft-FEWS Stand alone and check if you can import the data again. If you succeeded, make sure the client.truststore file is also copied to your Forecasting Shell Servers.
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