When trying to forward a email one of users recieves the following message: You are not allowed to send this message because you are trying to send on behalf of another sender without permission to do so. Please verify that you are sending on behalf of the correct sender, or ask your system administrator to help you get the required permission. The user is sending the a recieved email as a forward from her own account. Any ideas on how to fix this? Much appreciated.

What about this e-mail makes it "certain"?Ed Crowley MVP "There are seldom good technological solutions to behavioral problems."

Sorry should of been more clear. The user said it only seems to happen when they recieve emails from certain users with attachments.

hi, What exchange server version & Mail client you are using..?Regards, Ajaj Desai (India)

hi, If you are using exchange 2k7/2k10 do the following settings. Set send-as permission below- Add-ADPermission "Ajaj Desai" -ExtendedRights Sends-As -User Ajaj.desai Set mailbox permissions below- Add-MailboxPermission "Ajaj Desai" -AccessRights FullAccess -User Ajaj.desaiRegards, Ajaj Desai (India)

Hi Ajaj, We're using 2007. The user already has these permissions. Any other ideas? Thanks for your help!

Are these "certain users" internal or external? Do they share anything in common?Ed Crowley MVP "There are seldom good technological solutions to behavioral problems."

Do you have RMS?MCP, MCSE 2000 , MCSA 2000 ,MCSA 2003 , MCITP , MCTS , MCT

They are internal and across differnent departments. No we don't use RMS.

Hi, Based on your description, I understand that when you try to forward email which contains an attachment, you will receive the following error: You are not allowed to send this message because you are trying to send on behalf of another sender without permission to do so. Please verify that you are sending on behalf of the correct sender, or ask your system administrator to help you get the required permission. Please help collect the following information for finding out the root cause: 1. Does your organization is a native Exchange 2007 environment? And what SP level? 2. What mail client are you using? And what version? 3. Which type of attachment in your email? 4. Does the issue reproduce when you forwarding an email without the attachment which receives from the certain user? 5. Does the issue reproduce when you forwarding an email with the same type attachment which receives from another user? And as per my research, the issue may occur if one or more of the following conditions are true: · The “Everyone” group is missing from the Security tab, at the Organization level · The “Authenticated Users” group is missing from the Security tab, at the Organization level · The “Everyone” and “Authenticated Users” groups are present at the Organization level but have not been granted the appropriate permissions · The “Everyone” and “Authenticated Users” groups are present at the Organization level and have also been granted the appropriate, but the permissions are not propagating down to the mailbox store level To resolve the issue, use ADSIEDIT tool to assign the following permission to the “Everyone” group. · Create named properties in the information store · Create public folder Apply these SPECIAL permissions to the "Everyone" group: In the "Apply onto" field select "Private Information Store objects" · List Contents · Read All Properties · Read Permissions Apply these SPECIAL permissions to the "Everyone" group: In the "Apply onto" field select "Public Information Store objects" · List Contents · Read All Properties · Read Permissions Assign these SPECIAL permissions to the "Authenticated Users" group: In the "Apply onto" field select "This object only" · Read All Properties Please note: You incorrectly modify the attributes of Active Directory objects, you can cause serious problems. These problems may require you to reinstall Windows server or Exchange server. Microsoft cannot guarantee that problems occur of you incorrectly modify Active Directory object attributes can be solved. Modify these attributes at your own risk. 1. Start the ADSI Edit tool. 2. Expand "Configuration Container", and then expand "CN=Configuration, DC=<Domain>, DC=<com>". 3. Expand "CN=Services", and then expand "CN=Microsoft Exchange". 4. Right-click "CN=<Organization>", and then click "Properties". 5. Click the "Security" tab. 6. Add appropriate permissions. Best regards, SerenaPlease remember to click Mark as Answer on the post that helps you, and to click Unmark as Answer if a marked post does not actually answer your question. This can be beneficial to other community members reading the thread.

Send on behalf isnt as Forwarding an email. Are u sure that they are forwarding the email. Could u try if the error occurs in OWA. Also check the from field for the user that has the issue. Is he sending as him or as someone else? rgd

Thanks guys. Serena: It's Exchange 2007 with SP2 The user is on Outlook 2007 The file is a .pdf 4. No 5. Yes Zarko They aren't using the send on befalf feature they are using their own account. Thanks,