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Applets Provoke "Java.io.IOException : Unable To Tunnel Through Proxy. Proxy Returns "HTTP/1.1 403 Forbidden" When Started (Doc ID 2024793.1)

Last updated on JANUARY 22, 2025

Applies to:

Java SE JDK and JRE - Version 6 and later
Information in this document applies to any platform.

Symptoms

Applet startup failure upon upgrading the JRE from 6 update 51 to 7 update 79.


 
Other observations:

Users are able to access https://applet.xxx.net:9552/forms/java/webicons01.jar directly via browser.
Problem goes away on client when reverting back to Java SE 6u51 (i.e. reverting only the Java version on client).
Problem goes away on Java SE 7u79 if Proxy PAC file not used. Problem returns when PAC file used.



Cause

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In this Document
Symptoms
Cause
Solution
References


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