HTTP Error 500.19 - Internal Server Error

“HTTP Error 500.19 - Internal Server Error” is a common error that occurs in IIS (Internet Information Services) on Windows servers. This error indicates that the requested page cannot be served due to incorrect server configuration.

The “HTTP Error 500.19” most often specifically refers to a problem loading the application's configuration file (Web.config) or IIS configuration file (ApplicationHost.config).

This error can be caused by a different other factors, and troubleshooting can be challenging, especially for those who are not familiar with the underlying technology. In this article, we will look into the causes, precautions, diagnosis, and solutions for “HTTP Error 500.19 - Internal Server Error IIS”.

Causes of HTTP Error 500.19 - Internal Server Error

There are several potential causes of the “HTTP Error 500.19 - Internal Server Error”:

  • Incorrect permissions on the web.config file: The application pool identity may not have read access to the web.config file. This is required in order to load the configuration settings.
  • Incorrect authentication settings in IIS: If anonymous authentication is not enabled correctly or authentication settings are misconfigured, it can cause this error.
  • Syntax errors in web.config file: Simple typos or incorrect XML formatting in the web.config file can trigger HTTP Error 500.19 error.
  • Incorrect application pool identity: If the app pool is running under an account that does not have access to required resources, it may fail to load web.config.
  • Multiple IIS sites using same web.config: If multiple sites point to the same physical web.config file, they may overwrite settings or cause access conflicts.
  • Exceeded maxAllowedContentLength limit: Large request bodies may exceed configured size limits, preventing web.config from loading.
  • Invalid .NET version: The application pool must be configured to use a compatible .NET version for the application. .NET helps run ASP.NET applications. An outdated version can trigger this error.
  • Conflicting rewrite rules in web.config: The web.config file contains rewrite rules that direct URL requests. Conflicting rules here can cause HTTP Error 500.19 error.
  • Incorrect handlers mapped in IIS: Handlers help IIS determine how to process requests for specific file types. Incorrect handler mappings will lead to HTTP Error 500.19.
  • Invalid machineKey configuration: The machineKey element in web.config must be configured properly where required.
  • Custom HTTP modules: Badly coded or incompatible HTTP modules can disrupt configuration file loading.
  • Incorrect NTFS permissions: The IIS worker process account requires NTFS to read and execute permissions. Incorrect permissions will result in HTTP 500.19 errors.
  • Missing or corrupted files: If files required to process requests are missing or corrupted, it may lead to “HTTP Error 500.19 - Internal Server Error”.
  • Application pool recycling: Rapid recycling of application pools can cause this error by not giving apps enough time to load properly.
  • Server resource exhaustion: Low disk space, memory, and CPU overuse can trigger internal server errors.

So in short, the main causes of “HTTP Error 500.19 - Internal Server Error” can be misconfigured IIS settings and authentication, file permissions, syntax errors, identity conflicts, configuration issues, rewrite rules, custom modules, problems with required file access, and resource constraints on the server.

Precautions Before Troubleshooting HTTP Error 500.19 - Internal Server Error

Before attempting to diagnose and troubleshoot the HTTP 500.19 error, some precautions and preparations should be taken:

  • Backup web.config / machine.config / ApplicationHost.config. Before making any config edits, backup these files in case changes make problems worse.
  • Check permissions on web.config and grant Read & Execute for the application pool identity.
  • Verify the application pool is using a compatible .NET version for the application.
  • Check for site conflicts if using the same web.config across multiple sites.
  • Validate XML formatting for web.config using an online parser to check for syntax errors.
  • Review recent configuration changes or module installations that could have caused conflicts.
  • Check the IIS and application event logs for related errors.
  • Test any configuration changes on a staging server first before updating production.

These precautions help avoid making the problem worse when troubleshooting. Having backups and logging enabled are critical safety nets as well.

Diagnosing HTTP Error 500.19 Internal Server Error

Diagnosing the specific cause of HTTP Error 500.19 requires methodically checking several aspects of the IIS configuration and server environment:

  • Review error log details: The error logs generated by IIS and Windows Event Viewer provide crucial clues to diagnosing “HTTP Error 500.19 - Internal Server Error”. Error log entries should be examined in detail to pinpoint the likely cause.
  • Check site authentication settings: Confirm anonymous authentication is enabled correctly for the website in IIS (for public areas only). Also, verify any other authentication settings like Windows/digest authentication are configured properly where required.
  • Validate app pool identity permissions: The app pool identity account must have read/execute access to the website content. Check these folder/file permissions to ensure no access-denied errors.
  • Review IIS handler mappings: Handler mappings tell IIS how to process requests for specific file types or extensions. Incorrect mappings can lead to “HTTP Error 500.19 - Internal Server Error” so these settings must be double-checked.
  • Examine web.config rewrite rules: Improperly configured rewrite rules in web.config can conflict and cause 500.19 errors. Review all rewrite rules for potential issues.
  • Test .NET version requirements: Try switching the app pool to use a different .NET CLR version to see if it resolves the problem.
  • Check for missing or corrupt files: Verify files like web.config are not missing or corrupt. If they are, replace them with a known good copy.

Following this process should reveal the specific problem at the root of HTTP Error 500.19. The most common causes can be narrowed down for further investigation.

Solutions for HTTP Error 500.19 - Internal Server Error

Once the specific cause of HTTP Error 500.19 has been diagnosed, the appropriate solution can be applied:

Solution 1: Grant proper folder/file permissions:

If access denied errors are the cause, grant read/execute permissions for the app pool identity to the website folders and files. Grant appropriate permissions to the IIS user for the "web.config" file and its containing folder. This often resolves the Error HTTP 500.19 due to permission issues.

Solution 2: Update IIS handler mappings:

If handler mappings are incorrect, modify them to specify proper handlers for the application's file types.

Solution 3: Fix web.config errors:

If web.config rewrite rules or other settings are causing the issue, edit the file to fix the problems.

Solution 4: Install required .NET Framework:

If the .NET CLR version is outdated, install the required .NET version and assign the app pool to use it.

Solution 5: Resolve authentication conflicts:

If anonymous or other authentication settings are misconfigured, modify them to conform to the application's requirements and get fix “HTTP Error 500.19 - Internal Server Error”.

Solution 6: Recycle the app pool:

If configuration changes were made, recycle the app pool to clear the old settings and load the new ones.

Solution 7: Increase server resources:

If the server is resource-constrained, add RAM, CPU capacity, or disk space if needed to resolve performance problems.

Solution 8: Rollback recent changes:

If a new setting introduces the problem, roll back the changes to restore proper functioning.

Solution 9: Install Missing Modules:

If IIS throws the HTTP Error 500.19 - Internal Server Error due to a missing module, either install the required module or remove its reference from the "web.config" file.

Solution 10: Unlock Sections in Web.config:

Use the appcmd utility in IIS to unlock sections of the “web.config” that might be locked at a higher level, resolving the HTTP Error 500.19 Config file problem.

Solution 11: Update Application Pool:

Ensure your application is running in the correct application pool and with the right .NET version. This can mitigate issues related to the IIS HTTP Error 500.19 - Internal Server Error.

Solution 12: HRESULT error code:

As there could be a lot of reasons behind HTTP Error 500.19, using HRESULT error code like HTTP Error 500.19 - Internal Server Error 0x8007000d, we can search for the exact cause and get the solution. For the following HRESULT errors, we recommend you visit this official link from Microsoft to get the solution.

HRESULT codes:

  1. 0x8007000d
  2. 0x80070021
  3. 0x80070005
  4. 0x800700b7
  5. 0x8007007e
  6. 0x800700c1
  7. 0x8007010b
  8. 0x8007052e
  9. 0x80070003

With the correct solution applied for the specific HTTP Error 500.19 root cause, the internal server errors should be resolved and proper site functionality restored.


HTTP Error 500.19 has numerous potential causes that can be diagnosed through detailed log analysis and methodically checking IIS configurations. Once the root cause is identified, applying the corresponding troubleshooting solution will resolve the “HTTP Error 500.19 - Internal Server Error” and restore normal site operation. Carefully following error diagnostics and solution deployment steps will eliminate frustrating HTTP Error 500.19.