Error Fixed: 503 Valid RCPT Command Must Precede Data In Outlook

Outlook is one of the most preferred email clients owing to its vast database. It has become popular due to its exciting features and exceptional services. 

Despite being a popular email client technical glitches can occur. ‘Error 503: valid RCPT command must precede data’ is a common error faced by several users while trying to send an email. This error indicates that the SMPT connection is not properly authenticated by the email server. 

If you are also getting the same error and unaware of how to get rid of this error, you can have a quick look at the guide discussed below. Here, you will get the effective hacks through which you can troubleshoot this error in minutes. So, let’s begin. 

How to Fix Fix 503 Valid RCPT Command Must Precede Data

In this section, we are going to present two common ways to fix this error. You can have a look at the methods explained below: 

Fix 1: Check the Email Before Sending

When you open the Outlook mail, it starts to check the email automatically. But, if you are receiving the error 503 while trying to send an email, right after 30 minutes from opening the Outlook, then you need to check the new messages. 

Then, try to resend the emails and check if the error is resolved. Else, you can perform the next procedure stated below. 

Fix 2: Check the SMTP Authentication

As we mentioned above, the error ‘503 valid rcpt command must precede data’ may occur due to the misconfigured SMTP authentication. Usually, to configure the SMTP authentication of the email client, you need to edit the SMTP settings of the email account.  

You can do this easily by adding the email ID and password with the SMTP settings. Here are the steps you can perform to do this: 

1. First and foremost, open the Outlook mail and navigate to the File menu. Choose the ‘Account Settings’ option. 
2. Next, again tap on the ‘Account Settings’ option from the next page. Choose the email account that you want to set up and tap on the ‘Change…’ button. 
3. Go to the Outgoing Server tab by going to the ‘More Settings…’ option. Then, check the box that prompts ‘My outgoing server (SMTP) requires authentication’. 
4. Now, choose the ‘Use same settings as my incoming mail server’ option from the next page. Navigate to the Advanced tab and set the ‘Outgoing server (SMTP) port’ to 465. 
5. Afterward, tap on the ‘Use the following type of encryption’ drop-down arrow and choose the SSL option from the list. 
6. Tap on the OK button, it will navigate you to the ‘Internet E-mail Settings’ window. Tap on the Next and then Finish button to complete this procedure. 

Now, you can try to send an email to check if the issue is resolved. 

Additional Solution: 

If the above procedures fail to eliminate this error from Outlook mail, you can perform the hacks as follows: 

• Apostrophes: Remove the non-alphabetic characters or apostrophes from your Outlook email account to fix this error. 

• VPN: According to some users, they face this error while trying to send an email through a VPN network. Henceforth, you can disconnect the VPN network to get rid of this error. 

• Outlook PST Files: If there are any corrupted PST file in your Outlook account, then it may lead to this error. Try to repair this file to troubleshoot this error. 

After performing the above steps, you can check if the error is fixed. 

Summing Up…

In the above discussion, we have provided effective ways that can help you to solve this error. Both methods are quite easy to apply. We hope, the additional hacks will definitely assist you to put an end to this error. Furthermore, you can also share your valuable feedback in the comment section given at the end of this post.