After a recent upgrade to a non-Windows component, we started a seeing a few complaints of Windows Script Engine issues, manifesting themselves as Internet Explorer issues or the failure to execute VB scripts on the local workstations. After isolating the issue to a problem registry value for VBscript and JScript, the issue was resolved by re-registering these components. In doing so, I became a little curious about the whole regsvr32 process and did a little investigating into what happens when regsvr32 is executed.

For starters, think of an unregistered DLL like a person without an identity. You exist, but without a social security number, an address, or any other official documentation, you’re just not a functional part of society. If you want to work, contribute, or be known, you need to walk into the local social security office and start by getting an SSN (yes, the Windows registry is a bureaucratic institution).

I use Process Monitor to do a simple trace all regvsr32.exe operations¹. In the example here, I am going to unregister and then register a module. It doesn’t really matter which one, but I want to use one where the effects of unregistering it are obvious. I start by un-registering jscript9.dll, the Windows Script Engine for Internet Explorer 9. Read the rest of this entry »

Recently, we began seeing a several complaints about missing menus, missing form fields, and search failures in Internet Explorer after a recent upgrade to a component of our AV suite. One of these complaints came to my attention after one of my co-workers also was baffled by missing menus he could not account for in Kronos, an employee time management application that runs in Internet Explorer and relies on the Sun/Oracle Java platform, despite that fact that Java was reinstalled, along with the browser in an attempt to correct.

In all cases, I found that jscript.dll needed to be re-registered to correct. So the question became “Why didn’t installing Java handle that?” The short answer is Jscript is not Java. Jscript can be thought of as an implementation of the Microsoft Windows Script Engine (think VBScript, too). It is based on an open source programming language, ECMAScript, similar to JavaScript (also once known as LiveScript), which was created by Netscape. Some people like to say that MS Jscript was a rip-off of JavaScript, but this doesn’t hold since it is based on open source scripting language.

This Microsoft KB article states “…JScript is a high-performance scripting language designed to create active online content for the World Wide Web. JScript allows developers to link and automate a wide variety of objects in Web pages, including ActiveX controls and Java programs. Microsoft Internet Explorer is designed to interpret JScript embedded into Web pages.”

Anyways, if you are encountering similar issues and are at a loss to explain, try registering this DLL. In Windows XP, this can be done from a command prompt or the Windows Key+R by typing regsvr32 jscript. Read the rest of this entry »