Outlook can´t auto populate, signture lost and no attachment preview or open

Hi! Thanks for the quick response!

Regarding to your context question, bellow you will find my answers.

• As the question is under the Business tag, can you confirm if this is a Microsoft 365 work/school account or a personal account (hotmail, gmail, outlook.com,...)?
  • I´t´s a microsoft 365 work (It´s an account inside of a corporation)
• If it is a work/school account, are other users in your organization experiencing the same issue, or only your account?
  • No other issues, it happened to my after a windows update.
• When you try to open or preview an attachment, do you receive an error message? If so, please share the exact message or a screenshot, while hiding any personal or sensitive information.
  • "Something went wrong while creating the document preview" and also lost the link to the app to open the file.
• Does the attachment issue affect all attachments and file types, or only certain ones, such as PDF, Word, or Excel files?
  • All the attachments.
• Regarding auto-complete, are all previously suggested email addresses missing, or does Outlook simply no longer suggest newly entered recipients?
  • Just stop auto populate.
• For the signature, is the signature itself missing from Settings > Accounts > Signatures, or is it still there but no longer inserted automatically?
  • Dissapear from the accounts > signatures
• Were there any recent changes to your account, license, organization policies, or security settings before the issue started?
  • No, nothing in all the azure domain.

Since you posted your question in English , I’ll reply in this language as well. If you’re more comfortable using another language, please let me know, I’ll be happy to tailor my response to your preferred language.

Hello @Ezequiel Salvarezza,

Thank you for providing the details.

Based on your description, I did some research but could not find any official confirmation from Microsoft of a current issue matching all the symptoms you described. I also tested the relevant Outlook functionality with my own account, and it appears to be working as expected on my side.

Since you mentioned that the issue occurs across different computers, your phone, and Outlook on the web, it seems less likely to be caused by a specific Outlook installation or device.

To help better understand your environment and provide the most appropriate troubleshooting steps, could you please share the following information?

• As the question is under the Business tag, can you confirm if this is a Microsoft 365 work/school account or a personal account (hotmail, gmail, outlook.com,...)?
• If it is a work/school account, are other users in your organization experiencing the same issue, or only your account?
• When you try to open or preview an attachment, do you receive an error message? If so, please share the exact message or a screenshot, while hiding any personal or sensitive information.
• Does the attachment issue affect all attachments and file types, or only certain ones, such as PDF, Word, or Excel files?
• Regarding auto-complete, are all previously suggested email addresses missing, or does Outlook simply no longer suggest newly entered recipients?
• For the signature, is the signature itself missing from Settings > Accounts > Signatures, or is it still there but no longer inserted automatically?
• Were there any recent changes to your account, license, organization policies, or security settings before the issue started?

This additional context will help us understand your environment and narrow down whether these symptoms are related to the mailbox/account itself or an organization-level configuration.

In the meantime, if this is a work or school account, I suggest contacting your IT administrator first. Ask them to check and verify whether any recent policies, security settings, or configuration changes in your organization could be affecting your account.

Since the same behavior follows your account across multiple devices and Outlook on the web, I would not recommend reinstalling Outlook or Office at this stage.

If your administrator confirms that there are no relevant service incidents or organizational changes and the problem persists, I recommend asking them to open a support request with Microsoft for further investigation of the affected mailbox.

Please let me know the results and the additional information above, and we can continue narrowing this down together.

Best regards,