Can send emails & working offline

It sounds like you're experiencing a connectivity issue with Outlook. Here are some steps you can take to troubleshoot the problem:

1. Check Your Internet Connection: Ensure that your internet connection is stable and working properly since you mentioned you can receive emails.
2. Toggle Offline Mode: Since the offline button is grayed out and shows a red X, try the following:
   • Close Outlook and reopen it to see if the issue persists.
   • If the problem continues, check if there are any updates available for Outlook or Windows, as you mentioned both are up-to-date.
3. Run Microsoft 365 Diagnostics: You can run the Microsoft 365 Diagnostic tool to troubleshoot connectivity issues. This tool performs automated checks and can help identify the problem.
4. Check for Service Issues: If multiple users in your organization are having similar issues, it could be related to a service outage. Check the Microsoft 365 Service health status to see if there are any reported issues.
5. Repair Outlook Profile: If the above steps do not resolve the issue, consider creating a new Outlook profile or repairing the existing one, as corrupted profiles can cause connectivity problems.

If these steps do not resolve your issue, you may want to contact Microsoft support for further assistance.

References:

• Help Identify My Issue with Sending/Receiving Email in Outlook (Automatic Checks)
• Can't send or receive email in Outlook and "Metered Connection Warning" is triggered
• Fix Outlook connection problems for Microsoft 365 account

Hi Rachel Nichol

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

Based on your description, I understand that you are unable to send emails in Outlook and that the "Work Offline" button is stuck with a grayed-out Red X, even though you are receiving mail and have an active internet connection.

Since you have already tried a Quick Repair and verified your connection, this specific behavior (receiving but not sending, with a glitched Offline button) usually indicates a blockage in your Outbox or a corruption in the local data file (.ost).

Here are some recommended steps you can try:

Scenario A: Classic Outlook

Clear the stuck Outbox:

Sometimes a single email (or a large attachment) gets stuck in the outgoing process, causing the "Offline" status to freeze. Please try to open Outlook and go to your Outbox folder. If there are any emails sitting there, drag and drop them into the Drafts folder > Restart Outlook and see if the Red X disappears.

Launch Outlook in Safe Mode

This helps rule out any third-party Add-ins that might be blocking the send function.

• Close Outlook completely > Press the Windows Key + R on your keyboard > Type outlook.exe /safe and press Enter.
• If the Red X is gone and you can send email in this mode, an Add-in is the cause. Let me know if this works, and I can guide you on how to disable the specific culprit.

Refresh the Data File

Since you are using Microsoft Exchange, Outlook keeps a local copy of your mail on your computer. If this file gets corrupted, the "Send" pipe breaks. We will simply reset this file (Outlook will re-download your mail from the server automatically).

• Close Outlook and try to open the Control Panel.
• In the top right search bar of Control Panel, search for Mail. Open Mail (Microsoft Outlook).
• Click the Data Files... button.

• Select your email account in the list and click Open File Location (a folder window will pop up).

• Close the "Mail" setup box and the Control Panel (keep the folder window open).
• In the folder window, right-click the file associated with your email (it ends in .ost) and select Rename to.old (ex: ******@outlook.ost.old).
• Re-open Outlook.
  • Note: Outlook will say "Preparing mailbox for first use." This is normal as it recreates a fresh, error-free connection to the server.

Please let me know the results of these steps. If the issue persists, you can consider Create an Outlook profile - Microsoft Support.

Scenario B: New Outlook

Reset the App

Close Outlook and open your Windows Settings (Gear icon in the Start Menu). Go to Apps > Installed Apps. Search for Outlook (New) in the list and click the three dots (...) next to it and select Advanced Options.

Scroll down to the "Reset" section and click Reset.

(While there is a 'Repair' button, I recommend clicking Reset for this specific issue. Windows will show a warning that 'data will be deleted,' but please do not worry.

Since you are using the New Outlook, your actual emails and contacts are stored safely on the server. The 'data' being cleared is simply your local sign-in session and cache. You will just need to sign in with your email and password again after the Reset is complete)

Remove and Re-add the Account

If the reset does not fix the sending issue, we need to refresh the cloud link.

• Open the New Outlook > Go to the Settings (Gear icon) in the top right corner of the app.
• Select Accounts > Email accounts > Click Manage next to your email address and select Remove. Once removed, click Add Account to sign back in.

If I misunderstand anything, please correct me. I hope this information helps.

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Thank you for the above. I did check the outlook outbox and nothing there, I also opened in safe mode and sent an email from from outlook.com which I received in office outlook, however the reply would not go through and I get a system administrator error with the following: Microsoft.Exchange.Data.Storage.QuotaExceededException: Microsoft Unified Storage is full. I've check the storage for both Office and Microsoft and storage is only 3%.

I tried your suggest of resetting the date file, however there is no file with .ost

I have also reset the app and still having problems.