SMTP server internal error
SMTP server outlook mail causes basic issues with send/receive due to the security restrictions and some file folder corruptions. The basic troubleshooting includes checking the configuration settings and then test the protocols using test emails. The SMTP is a basic entity that corrupts quickly when there are changes on the Internet services. If you change the Internet service providers, issues may arouse with sending and receiving emails. Outlook program stops sending emails when port 25 is blocked by the firewall.
It is required to manually open the blocked ports to resume the services for outbound emails. It can be found under system management utility.

Few steps for fixing the outlook mails are as followed:-
Reasons behind non-working email system:
Some possible factors for reported threats like error attacks, bad sync, outlook data file error, and unknown bug.
Error solutions:
- Check your internet connection:
This is the primary analysis to proceeding the next steps. You can open internet explorer in windows pc open to any website to make a sure internet connection
- Remove the bad settings of outlook account.
Microsoft Outlook has a different version which is available at the user ends.
This process might deviate from one to another version in the same email clients.
Resolve any bad settings is application available and you can manipulate server settings also.
- Remove garbage emails.
Sometimes we are receiving spiteful codes on the mailbox. At this time we should delete this kind of email soon.
- Avoid clash with anti-virus
Sometimes antivirus plugins also obstruct the incoming or outgoing server, then we can follow the guidelines of antivirus manufacture to enable error similarity between antivirus to the client.
- Firewall softer set as a right priority
- Check email profile in outlook profiles
- Run outlook email client safe mode
- Use scan PST.exe for the reconstruction of the damaged outlook database.

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