.STL File Extension

File Type:
Certificate Trust List

Having trouble opening .stl extension? Don't panic! This page explains what stl files are as well as suggests programs you may use to open stl files. You can download these programs through this page.

What is a STL file?

Stl file extension has Certificate Trust List file type, developed by Microsoft, which is associated with the "web files" category.

Trust list file provides a list of predefined items, which have been all approved and signed by a trusted entity. 

To learn how you can open the given file, read the information below.

stl file icon
File Type:
Certificate Trust List
Web Files

How to open STL file?

Double click the stl file to open it. The file will open automatically if file associations have been correctly installed and there is a proper program on your computer; if not, file associations may be corrupted and your OS either cannot find the proper program, or you might not have one for opening the file. First, we recommend downloading our utility to fix file association errors; then, you can download any program for opening the .stl extension from the ones suggested below. If you are certain there is nothing wrong with the file associations, you may proceed to method 2 right away; besides, if you can't make up your mind when choosing the right program, use Universal File Viewer from the last method.

Method 1: Fix file association errors

Follow these steps in order to automatically fix the stl extension associations' problem in no time:

  • Step 1: Click on "Download Solution" to download automatic tool provided by WikiExt.
  • Step 2: Click "Start Scan" to identify all potential issues.
  • Step 3: Review scan results and click "Fix Items".

File Size: 3.04 MB, Download time: < 1 min. on DSL/ADSL/Cable

This Tool is Compatible With: Windows XP, Vista, 7, 8/8.1, 10

Method 2: Download the appropriate software

The given list provides programs which may be used for opening or converting the stl file. Choose the proper program for your OS, and click it to start the download or proceed to the developer's website.

Programs that open STL files

  • Windows Windows
    • Microsoft Internet Information Services (IIS) Microsoft Internet Information Services (IIS)

Method 3: Use universal file viewer

In addition to the list of programs above, we recommend using Universal File Viewer. This tool can open over 250 file extensions and, most likely, it will be able to open the stl file as well. Download Universal File Viewer for your OS.

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