How to fix Class not registered or 80040154 error

Last update: 25 Jun 2005 | 284993 views

"Class not registered" is one of the most annoying and frustrating error message I ever got because none of the video files can be played by Windows Media Player, Media Player Classic or other DirectShow player and common fix methods (Windows Media Player reinstallation/upgrade, codec reinstallation...) seems to fail.
Fortunately, the solution (in fact one of them because there are few different solutions) for this problem is very simple.

After some research I found that quartz.dll (a DirectX related DLL) wasn't registered correctly.

How to register it? Click on Start > Run... > and type regsvr32 quartz.dll

Run dialog box

In the end, you should receive a message saying that your file was succesfully installed.

The file was succesfully installed

Note: Please, let us know if the solution suggested here wasn't helpful for you so we can try to complete this guide with other hints.

| Report it!
on 15 Dec 2016, written by: Unnamed # 5

worked on a windows xp professional.

on 01 Sep 2016, written by: xitiz # 4

i found class not registered in attendance management software. I format and installed a new software but again same problem is detected what can I do plz help me

on 02 Sep 2015, written by: Ryan Middleton # 3

Windows 10 error message:
"The module "quartz.dll" was loaded but the call to DllRegisterServer failed with error code 0x80070005.

For more information about this problem, search online using the error code as a search term."

on 03 May 2015, written by: Aviral # 2

It didn't fix my problem but gave a error message as everyone else who have commented.I use windows 7 ultimate

on 05 Mar 2014, written by: Luna Lovegood # 1

This didn't work for me because I still get an error message that says: "Quartz DLL was loaded but call to DLL Register Server failed with error code 0x80070005. Now what???

Leave a comment See more comments ( 51 )

Post a comment about "How to fix Class not registered or 80040154 error".
Let other people know about your experience with it.
Leave a comment

Codecs.com is known also as Free-Codecs.com. All website reviews, graphics, design and logo are Copyright © 2004-2020 Codecs.com