Was this page helpful?
Thank you!

Comments or suggestions?

Enter Email Address (optional)

Error Code:80029c4a Description:Error loading type library/DLL.

When you try to open QuickBooks Desktop, you see this error message:

Why this is happening

This error usually occurs when a QuickBooks Deskop system file has been damaged or cannot be found. This can sometimes occur when an antivirus has incorrectly marked a QuickBooks Desktop system file as being infected with a virus.

On August 15, 2014, Avast! antivirus incorrectly flagged the DMUSERS.DLL QuickBooks file as being infected and quarantined the file. This will cause this error to occur.

If you get this message after installing the QuickBooks 2016 R9 release, go directly to Solution 4.

How to fix it

Solution 1: Perform an Avast Virus Definition and Program Update:

  1. Right-click on your Avast icon in the icon tray in the lower right hand corner.
  2. Choose Update.
  3. Click Program and follow the prompts to update the Avast program.
  4. Repeat steps 1-3 above and choose Engine and Virus Definitions.

Solution 2: Check your antivirus program for files that have been quarantined.

For directions for other antivirus programs, please consult your Anti-virus help documentation.  NOTE:  Intuit recommends you contact an IT professional before making any edits to your anti-virus programs.


Solution 3: Run Reboot.bat.


Solution 4: Perform a clean install of QuickBooks Desktop.

If you've encountered this issue, resolved or not, please sign up below to be notified of updates to this issue.


Latest Update:

This Issue is being investigated at this time. We are in the early process of researching the concern

Next Update:

Monday, 1/16/2016 3:00 PM PST

KB ID# SLN41083
4/30/2017 2:01:10 AM
QYPPRDQBKSWS07 9138 Pro 2017 a04784