Error "There is no script engine for file extension" when running .js files

Symptom

When you attempt to run a .js (JScript Script File) file, one of the following errors may occur:

Can't find script engine "JScript" for script "filename.js".

There is no script engine for file extension ".js".

Resolution

This happens if the .js file class data is missing or incorrect. Follow these steps to resolve the problem:

Instructions for Windows Vista

Open an Elevated Command Prompt window. To do so, click Start, click All Programs, click Accessories, right-click Command Prompt, and then click Run as administrator.

• Type the following command and press ENTER:

regsvr32 %systemroot%\system32\jscript.dll

• Type EXIT to close the Command Prompt window
• Download vista_js_fix.reg from the Attachments section (scroll below), and save it to Desktop
• Right-click vista_js_fix.reg and choose Merge
• Click Yes when asked for confirmation.

Instructions for Windows XP

• Click Start, Run and type:

regsvr32 %systemroot%\system32\jscript.dll

• Press ENTER
• Download xp_js_fix.reg from the Attachments section below, and save it to Desktop
• Right-click xp_js_fix.reg and choose Merge
• Click Yes when asked for confirmation.

If the above does not solve the problem, then download and install Windows Script 5.7 from the following Microsoft Web site:

Download details: Windows Script 5.7 for Windows XP