The Snowflake account URL is incorrect or uses the wrong regional endpoint. Outbound TCP port 443 is blocked by a firewall or security group rule. A proxy server is configured incorrectly and refusing the forwarded connection. The Snowflake account is suspended or decommissioned. A network appliance (WAF, DLP) is blocking connections to snowflakecomputing.com

Verify the account URL: it should be .snowflakecomputing.com — confirm the account identifier in Snowflake Admin > Accounts.. Test TCP connectivity: telnet .snowflakecomputing.com 443.. Check firewall rules for outbound port 443 to *.snowflakecomputing.com.. If using a proxy, verify jdbc:snowflake://... includes the correct proxy parameters or set JVM system properties.. Check the Snowflake status page (status.snowflake.com) for service availability in your region.

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Power BI Refresh Error:
JDBC 1

What does this error mean?

The JDBC driver cannot establish a TCP connection to Snowflake. The remote endpoint is actively refusing connections, typically due to a network misconfiguration, incorrect account URL, or firewall blocking port 443.

Common causes

1The Snowflake account URL is incorrect or uses the wrong regional endpoint
2Outbound TCP port 443 is blocked by a firewall or security group rule
3A proxy server is configured incorrectly and refusing the forwarded connection
4The Snowflake account is suspended or decommissioned
5A network appliance (WAF, DLP) is blocking connections to snowflakecomputing.com

How to fix it

1Verify the account URL: it should be <account>.snowflakecomputing.com — confirm the account identifier in Snowflake Admin > Accounts.
2Test TCP connectivity: telnet <account>.snowflakecomputing.com 443.
3Check firewall rules for outbound port 443 to *.snowflakecomputing.com.
4If using a proxy, verify jdbc:snowflake://... includes the correct proxy parameters or set JVM system properties.
5Check the Snowflake status page (status.snowflake.com) for service availability in your region.

Frequently asked questions

What is the correct format for the Snowflake JDBC URL?

jdbc:snowflake://<account>.snowflakecomputing.com/?db=<db>&warehouse=<wh>&role=<role>. The account identifier format depends on your region — check Admin > Accounts in the UI.

Do I need to whitelist specific IPs for Snowflake?

Snowflake publishes its egress IP ranges. For inbound network policy rules, add the Snowflake CIDR ranges. For outbound client-to-Snowflake, allow *.snowflakecomputing.com on port 443.

Official documentation: https://docs.snowflake.com/en/user-guide/client-connectivity-troubleshooting/error-messages