Outlook no longer opens my files in the desktop apps

I will answer you in English based on your question description. As a friendly suggestion, posting in Spanish may help your question reach a wider audience and increase the chances of receiving assistance from other community members. 

Hello @Arreola, Rolando ,

I hope you're doing well and thank you for sharing the details.

Before jumping into any conclusion, could you please provide the following information:

• Whether you are using New Outlook for Windows.
• Your current Microsoft Edge version.
• Whether the behavior occurs with all attachment types or only specific file formats such as Excel or PDF files.
• Whether the affected attachments are stored in Exchange email only or are linked from OneDrive/SharePoint.

This additional information would help determine whether there is any separate client-side factor contributing to the behavior.

Based on the behavior described, it appears that the attachment-opening experience in New Outlook for Windows may be affected by a recently identified service-related behavior associated with systems running Microsoft Edge version 156.

Impacted users may receive a message indicating that the file cannot be opened and that Outlook should be restarted. In some cases, the Open option for attachments may also become unavailable, which can result in files being downloaded instead of opening directly in the desktop application.

A service-side adjustment has already been deployed, and the change is currently being applied across the service infrastructure. Once the update has propagated, closing and reopening New Outlook should allow the updated configuration to take effect.

If you have Microsoft 365 administrator privileges, please sign in to the Microsoft 365 Admin Center using this link to view the details of this issue.

Alternatively, follow these steps:  

• Sign in to the Microsoft 365 Admin Center.
• Go to Health > Service Health.
• Search for Issue ID: EX1528992.
• Select the issue and expand the details to review the latest updates, impact, and remediation information.

As a temporary workaround, selecting "Save As" to download the attachment locally and then opening the file directly is expected to bypass the behavior.

I hope this information helps. If you need any further assistance, please feel free to leave a comment.

Kind regards.

Hello, good day!

Yes, I am using the (New) version of Outlook.

Here are the versions I have

And it happens with all kinds of files; I get that error.