Summary

The "Unable to Read Post Processor" error indicates that GibbsCAM was unable to read the selected post processor file. This typically occurs because the post processor file is corrupted, not licensed for the current computer, or is being locked by another application before GibbsCAM can access it.

In many cases, antivirus or endpoint security software is preventing GibbsCAM from reading the post processor file.

Table of Contents

Before You Begin

Before troubleshooting:

  • Close all instances of GibbsCAM.

  • Verify that you are using the correct post processor for your machine and license.

  • Ensure you have permission to access the folder containing the post processor files.

Note: Post processor files typically use the .POST or .EPOST file extensions.

Cause

This error is commonly caused by one of the following:

  • The post processor file is corrupted.

  • The post processor is not licensed for the current computer.

  • Antivirus or endpoint security software has locked the file.

  • Another Windows process has exclusive access to the post processor file.

  • The file cannot be read due to insufficient permissions.

Procedure

Step 1 – Verify the Correct Post Processor

Confirm that the selected post processor is intended for your machine configuration and is licensed for your installation of GibbsCAM.

If necessary, test with another known-good post processor.


Step 2 – Temporarily Disable Antivirus or Add File Exceptions

Temporarily disable your antivirus software or create exclusions for the following file types:

  • .POST

  • .EPOST

After creating the exclusions, restart GibbsCAM and attempt to post again.

Warning: Follow your organization's IT security policies when disabling antivirus software.

Expected Result

If security software was preventing access, the post processor loads successfully.


Step 3 – Determine Whether Another Application Has Locked the File

If disabling antivirus does not resolve the issue, determine whether another application has the post processor file open.

Microsoft Process Explorer can be used to identify which process currently owns the file.

Recommended workflow:

  1. Launch GibbsCAM.

  2. Open the Post dialog.

  3. Select the desired post processor.

  4. If the error does not appear immediately, attempt to post the program.

  5. When the error appears, open Process Explorer.

  6. Search for the name of the post processor file to determine which application has locked it.

Expected Result

The application holding the post processor file open is identified.


Step 4 – Close the Locking Application

After identifying the application that owns the file:

  • Close the application if possible.

  • Configure it to ignore .POST and .EPOST files if appropriate.

  • Restart GibbsCAM and test posting again.

Expected Result

The post processor can be opened and used normally.

Expected Result

GibbsCAM successfully reads the selected post processor and generates NC code without displaying the error.

Additional Information

Why Does This Happen?

Before posting, GibbsCAM must open and read the selected post processor file.

If another application prevents GibbsCAM from accessing the file—such as antivirus software, endpoint protection, backup software, or another utility monitoring the folder—Windows may deny access, causing this error.

Common Issues

This error is commonly associated with:

  • Antivirus software scanning post processor files.

  • Endpoint protection software locking files.

  • Corrupted post processor files.

  • Incorrect or incompatible post processors.

  • File permission issues.

Best Practices

  • Store post processor files in trusted folders.

  • Exclude .POST and .EPOST files from antivirus real-time scanning when permitted by your organization's security policies.

  • Avoid opening post processor files in multiple applications simultaneously.

  • Verify that custom post processors are compatible with your GibbsCAM version.

Troubleshooting

  • Problem: The error occurs with only one post processor.

Possible Causes

  • The post processor is corrupted.

  • The post processor is incompatible.

  • The post processor is not licensed.

Resolution

Test with another post processor. If the alternate post works correctly, replace or obtain a new copy of the affected post processor.


  • Problem: All post processors produce the error.

Possible Causes

  • Antivirus or endpoint security software is locking the files.

  • Another application has exclusive access to the files.

Resolution

Temporarily disable antivirus or use Process Explorer to identify the application locking the files.


  • Problem: The error continues after disabling antivirus.

Possible Causes

  • Another Windows process is holding the file open.

  • File permissions prevent access.

Resolution

Use Process Explorer to identify the locking process and verify Windows file permissions for the post processor folder.

Explore More from CAMCO

Visit the CAMCO website to learn more about:

Keywords

Unable to Read Post Processor, Post Processor Error, POST File, EPOST File, Unable to Load Post, Process Explorer, Antivirus, File Locked, Posting Error, NC Post