Resolving Incompatibility with Windows's ProxySettingsPerUser

Environment

Description

Q: Fiddler Everywhere does not capture traffic when a group policy sets ProxySettingsPerUser=0 (Windows OS).

Q: The Fiddler Everywhere logs contain the following error:

[2020-06-19 08:09:18:109] [Information] [Fiddler] Fiddler.Network.AutoProxy> AutoProxy Detection failed.
[2020-06-19 08:09:18:109] [Information] [Fiddler] AutoProxy failed. Disabling for this network.

What causes the issue, and how can it be resolved?

Solution

Sometimes, your system administrator can create a proxy group policy by setting ProxySettingsPerUser to 0. This means that instead of the default Windows behavior (each user has their proxy settings), all user accounts share one set of proxy settings. In this case, a value named ProxySettingsPerUser exists inside the following registry key:

HKLM\SOFTWARE\Policies\Microsoft\Windows\CurrentVersion\Internet Settings\ 

To resolve the issue, apply one of the following solutions:

• Run Fiddler Everywhere as admin

OR

• Change the value of the registry entry to 1 or delete the whole entry ProxySettingsPerUser