ODBC links between Excel files no longer work after update KB5002820

For your convenience, the below response is provided in English. If you prefer using French, please let me know.

Hi @François Boissonneault,

Thank you for posting your question in the Microsoft Q&A forum.

I'm sincerely sorry for any inconvenience and troubles this situation may have caused you.

Based on your sharing, the issue is highly due to missing compatibility between ODBC and the latest update KB5002820 patch (released on December 9). I have researched through Microsoft product help and other official information sources but up to now, there is no Microsoft help article or announcement found and also no troubleshooting guidance addressing this issue.

Therefore, to avoid negative effect this issue may cause to your workflow, I highly suggest rolling back to the previous Office version in which OBDC has worked properly:

Step 1: Download and Extract ODT 

• Open Excel then go to File > Account > note the version and build number you're having
• Download the .exe file from Download Office Deployment Tool from Official Microsoft Download Center 
• Run it to extract two files: setup.exe and configuration.xml (sample) 

Step 2: Create Your Custom Configuration File 

• Open Notepad and paste the following XML: 

<Configuration>  

<Updates Enabled="TRUE" TargetVersion="16.0.xxxxx.yyyyy" />  

</Configuration> 

• Replace TargetVersion with the exact build number for an earlier version compared to your current one. You can find this from Update history for Microsoft 365 Apps (listed by date) - Office release notes | Microsoft Learn. 
• Save the file as Config.xml in the same file location as the Setup.exe file 

Step 3: Run the Installer 

• Open Command prompt as administrator, navigate to the folder where setup.exe and your XML file are located, then run: 

setup.exe /configure config.xml 

• This will install the specified version of Office/Excel. 

Step 4: Update Office to the earlier version

• Open Excel > File > Account > Update options > Update Now.
• You can also select Disable updates to prevent reverting to newer versions.
• Microsoft official guideline: How to revert to an earlier version of Office - Microsoft Support

For better visualization about this guidance, you can watch this video How To Roll Back Microsoft Office To The Previous Version

(Note: We're providing this information as a convenience to you. The sites are not controlled by Microsoft, and we can't make any representations regarding quality, safety or suitability of any software or information found there. Please make sure you completely understand the risk before retrieving any suggestions from the above link) 

Additionally, I strongly recommend submitting in-app feedback so that your experience can be formally logged with our engineering team. You can do this from Excel > Help > Feedback or go to Microsoft 365 Feedback Hub > send feedback. 

For now, I highly recommend upvoting this answer as well. That way, other users who encounter the same question will see the clarification, and more of them may report similar problem, helping to bring attention to the request. The more reports the team receives, especially from business users, the faster issues like this can be prioritized and resolved as soon as possible. 

I know this is not the experience you expected, and I want to thank you for your patience while the team works on improvements.  

Thank you for your understanding and corporation. Please let me know if there's anything else I can help you with. 

Looking forward to your response.

 If the answer is helpful, please click "Accept Answer" and kindly upvote it. If you have extra questions about this answer, please click "Comment".   

Note: Please follow the steps in our documentation to enable e-mail notifications if you want to receive the related email notification for this thread