This article applies to dedicated and VPS customers only. Shared hosting customers already have this configuration enabled.
Unable to View Detailed ASP.NET Errors Remotely
If you cannot see detailed ASP.NET 4.x error messages on a remote machine — even after setting customErrors mode="Off" in your web.config — your server is likely running in retail mode. This is the default security configuration on Windows Server installations.
Retail mode suppresses detailed error output for remote requests, showing only generic error pages.
How to Enable Detailed ASP.NET Errors Remotely
To allow detailed error messages to appear remotely, you must update the machine.config file on your server.
- Open the machine.config file located in:
C:\Windows\Microsoft.NET\Framework\v4.0.30319\Config
and for 64‑bit:
C:\Windows\Microsoft.NET\Framework64\v4.0.30319\Config - Find the line:
<deployment retail="true" /> - Change it to:
<deployment retail="false" /> - Save the file and restart IIS if necessary.
After making this change, detailed ASP.NET error messages will be visible when accessing the site remotely.
Why Retail Mode Is Enabled by Default
- Prevents sensitive error details from being exposed publicly.
- Ensures production servers do not leak stack traces or configuration paths.
- Provides a safer default environment for new deployments.
On dedicated and VPS servers, you have full control and can safely disable retail mode for debugging.
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