Microsoft Outlook is a powerful email client that is trusted globally by businesses and individuals. Even though it is loaded with powerful security features, it is prone to errors. The ‘Permission Denied’ error is one of the issues that pops up while sending an email from the shared mailbox. Arising mainly because of the insufficient permissions issue, this error not only hinders smooth email communication but also hampers productivity.

In this guide, we will explore possible reasons behind the “You do not have permission to send the message” error. This guide will also shed light on the different methods available to fix this error. Besides this, we will also discuss how to rebuild the OST file as well as how to extract mailbox items from an orphaned or inconsistent OST file to a new profile or PST file.

Reasons for “Permission Denied Error” when Sending Emails in Outlook:

In this section, we will unearth probable causes behind permission-denial errors while shooting emails in Outlook. Some of them are listed below:

• Permission Issues: Sometimes inadequate permissions are the main reason behind this error message. When the user tries to send an email, instead, he is greeted by an error message reading, “You don’t have permission to send messages from this mailbox.” It means that the user lacks ‘Send As’ or ‘Send on’ Behalf permissions. Even if the user enjoys ‘Full Access’ permission on a shared mailbox, it doesn’t mean he also has the permission to send messages; he has only read and manage rights.
• Permission Delay: Previously the user was granted ‘Full Access’ permission but lacked ‘Send As’ or ‘Send on’ permissions so he was receiving the error message. Now, he is granted all permissions, but still, the error message keeps disturbing him. This is a permission delay issue, and it happens because the permissions take at least 60 minutes for implementation.
• Policy Restrictions: There is a policy in some organizations to restrict certain Outlook actions. Sometimes sending emails from the shared mailboxes are also restricted. 
• Antivirus or Firewall Interference: Antivirus or firewalls installed in the system or network, sometimes hinders with the operational functionality of the Outlook. Sometimes, it also hampers Outlook’s ability to send emails by flagging outgoing messages as threats. 
• Other Issues: Some other issues, like issues with the mail server or wrong email settings, can also cause this error. A corrupt Outlook profile or damaged Outlook data file (OST) may also lead to this error message.

Resolving ‘Permission Denied’ Error in Outlook:

After understanding possible causes of ‘Permission Denied’ error while attempting to send email from the shared mailbox, let’s move on to discuss possible remedies available to fix this issue. The step-by-step guide to fix this issue is listed below:

Fix 1: Check ‘Send on behalf’ and ‘Send as’ Permission Status:

As stated in the previous section, if a user doesn’t enjoy ‘Send on behalf’ and ‘Send as’ rights, he or she won’t be able to send email messages from the shared mailbox. Reach out to the administrator to check whether you have the required permissions. If you don’t have permission, ask the administrator to assign it. The steps to assign “Send As” permissions are listed below:

• Log in to the EAC (Exchange Admin Center) and go to ‘Recipients’
• Choose the Mailboxes or Shared tab to look for the mailbox for which you require access to rights
• Select the Shared Mailbox or User Mailbox and click Edit
• Click “Mailbox delegation” and then press the “(+)” icon
• Look for the user who needs permission, and then proceed on to select the user
• Select ‘Send As’ in the permission type option and press the Save button to apply the changes
• Follow the same process to add ‘Send on Behalf’ permissions

Fix 2: Verify Outlook Web App (OWA) Permissions: 

In some cases, Outlook users were unable to shoot an email message receive permission-denied errors even after having correct permissions. In this case, we need to check if the server is available/online by logging into Outlook on the Web (OWA). Follow the steps below:

• Login to Outlook on the Web (OWA) to verify if the server is online
• If OWA is unavailable, it means that the server is down for maintenance or a regular restart
• Wait some time for the server to come back online before trying to send emails again

Fix 3: Verify Outlook Data File Permissions:

Another factor that can cause permission denied error is missing read/write data file permissions. In order to troubleshoot this issue, we need to check and verify the status of the Outlook data (OST) file permissions. Follow the below steps to check and authorize the permissions:

• Exit the Microsoft Outlook app
• Press the Windows key + R
• In the Run dialogue box type “%localappdata%\Microsoft\Outlook
• This action will open the File Explorer window, featuring the visible OST file
• Hover the cursor on the OST file and choose Properties
• Make sure that the Read-only checkbox is unchecked
• Explore the ‘Advanced’ tab and make sure that the “Encrypt content to secure data” is unchecked
• Click Apply > OK

Fix 4: Rebuild Offline Outlook Data File (.ost):

If the above-mentioned methods are unable to fix the issue, then the next method is to rebuild the OST file. Follow the below steps for the same:

• Exit Outlook and launch the Run App by pressing Windows key + R.
• Type %localappdata%/Microsoft/Outlook in the Run dialogue box and press Enter key or click OK.
• Rename the original OST file. Add the a.bak extension to the end of the file name to create a backup.
• As an alternate solution, you can also cut and paste the OST file into a different folder or drive for backup purposes.
• Launch the Outlook app again.
• Since the original OST file has already been moved and renamed, Outlook will create a new OST file automatically and sync (download) all mail items from the mailbox server.
• Once the sync process is over, you can try to send a new email and check if the issue is resolved.

Now, it is the time to check and validate all mailbox items in the new OST file/Outlook profile. In case you come to know that some mail items are missing or lost in the OST file rebuilding process, you can use an expert-recommended tools that can scans and convert OST to PST in few easy clicks.  Later you can import converted PST file into Outlook via the Outlook Import/Export wizard.

Conclusion:

Many users frequent ‘Permission Denied’ error in Outlook. It occurs when the user sends a new email message from a shared mailbox. Main reasons of this issue include insufficient permissions or delayed permissions. Firewall or antivirus restrictions as well as mail server error or wrong email settings can also result in this error message. 

The above post also brings forth some methods to troubleshoot this error ranging from ‘Send on behalf’ and ‘Send as’ permissions and verifying Outlook data file permissions and updating Outlook client. When none of the methods works, go for rebuilding the Outlook data file (OST). There is a possibility that some mailbox items go missing during the troubleshooting process. To restore those missing items, you can use Stellar Converter for OST, which converts OST file into PST format with free preview. Loaded with advanced filter option, it saves the mailbox data in various formats like EML, MSG, RTF, HTML, and PDF.