Outlook is a great email client that helps to manage your daily tasks. If your work productivity is also affected by Error 503 valid RCPT command must precede data while sending or receiving emails, just follow our troubleshooting guide to fix it ASAP.
How to Fix Outlook Error 503 Valid RCPT Command Must Precede Data
When the recipient’s email server does not recognize your email address, you get this message.
- Your email server wants you to check your email first before sending it from your Outlook account. Doing so helps your email provider to manage the security of your email account.
- The error can also occur if your email account is not set up for SMTP Authentication.
- If you have enabled VPN on your device, it can also trigger error 503.
Method 1: Verify Email Before Sending
The first step involved in fixing 503 valid RCPT command must precede data error is to check your email messages.
1. Open your Outlook account and click on the File option.
2. Next, click on the Account Settings option.
3. Now, click on the Menu Setting option.
4. Finally, open the Advanced tab and uncheck the box for Do not save copies of sent items.
5. Click on OK and try resending your email or refreshing the mailbox to check if the error has been resolved.
Method 2: Disable VPN
If your system is trying to connect to a VPN or if you have enabled VPN on your PC, you must disable it to fix 503 valid RCPT command must precede data Office 365. Even though a VPN connection helps to make you anonymous online, it can malfunction at any time due to some security measures and result in error 503 on your email client. Therefore, it is best advised to turn off your VPN which you can do with the help of our guide on How to Disable VPN and Proxy on W1indows 10.
Also Read: 8 Ways to Fix Outlook This is not a Valid File Name Error
Method 3: Remove Apostrophes
Many email client users have also been able to fix Outlook error 503 by removing apostrophes.
- You must remove apostrophes while inputting the name of the recipient for the email.
- You can also ask the sender of the email to remove any if they are not able to send an email to you.
Method 4: Confirm Before SMTP
To know how to repair 503 error in Outlook, you must confirm if there are any new messages in your mailbox before sending a new mail to someone.
- While using Outlook, press the F9 key on your keyboard.
- Now, reboot your email service.
- Run the spam filter on the email application which takes about 30 minutes to get complete.
- Also, allow the email client to reset to send emails as previously.
- Once done, try to resend the email to check if the error has been resolved.
Method 5: Set Up SMTP Authentication
The next method involves setting up SMTP authentication to fix 503 valid RCPT command must precede data cPanel error. To configure SMTP authentication in your email client, you must edit your email account SMTP (outgoing mail) settings. You can add your email address and password to the SMTP settings and fix error 503 on Outlook with the help of the following steps:
1. Open Outlook 2016 on your Desktop.
2. Now, click on the File tab and select Account Settings to further open Account Settings…
3. Now, in the Account Settings window, click on the email account you wish to set up and select Change…
4. Next, in the Change Account window, click on the More Settings… button.
5. In it, click on the Outgoing Server tab.
6. Next, check the option for My outgoing server (SMTP) requires authentication.
7. Next, select Use same settings as my incoming mail server.
8. Now, click on the Advanced tab in the next window.
9. In it, set the Outgoing server (SMTP) port to 465 and select SSL in the Use the following type of encryption drop-down menu.
10. Now, click on OK.
11. Finally, on the Internet E-Mail Settings window, click Next and then Finish.
Also Read: Fix Signature Button Not Working in Outlook
Method 6: Try Official Outlook Repair Tool
Finally, if none of the methods seem to help resolve 503 valid RCPT command must precede data Office 365 error for you then try the official Outlook repair tool for your email client. Using this method will help you to repair corrupted PST files, repairs, and restores all mailbox contents speedily. You can visit the official Repair Outlook Data Files page and follow the instructions to fix error 503 on Outlook.
Frequently Asked Questions (FAQs)
Q1. What does error 503 mean in Outlook email?
Ans. Error 503 in Outlook means that the issue is related to the local network or restrictions on a corporate network which is interfering when you try to log in to your Microsoft account.
Q2. What does it mean by error 503 while sending Outlook mail?
Ans. Error 503 while sending Outlook mail occurs if the email client does not authenticate with the email server.
Q3. What does it mean by error 503 in Microsoft Online?
Ans. Error 503 in Microsoft Online means that the server is not ready to handle the request.
Q4. How can I fix Outlook sending error?
Ans. Yes, You can fix an Outlook sending error by making sure you are connected to the internet, by making sure your email account settings are correct, and by deleting suspicious mail from your mailbox.
Q5. Why does Outlook block me from sending emails?
Ans. Outlook might block you from sending emails if your email address is suspected of sending spam.
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This brings us to the end of our guide on Outlook error 503. We hope that we were able to answer all your queries about error 503, why it occurs, and different methods of fixing it. Do let us know about your thoughts and if you have any other queries, leave them below in the comments section.
