Restore Microsoft SMTP on Ubuntu

@versacode

We can assist with restoring outbound mail from your Ubuntu VPS via Microsoft SMTP. We will methodically check connectivity, TLS negotiation, credentials, and port availability. We will apply the minimal fix and document the exact changes. We use SSH and mail logs for diagnostics. Experience: We are a group of engineers with 18+ years of experience in software development, web development and system administration. We are familiar with Ubuntu server configurations and SMTP integration.

@anirudhat

Hi, I've dealt with this exact scenario before—Microsoft SMTP silently dropping outbound mail from a Linux VPS, with clean logs and no obvious errors, usually points to a stale OAuth token or an expired app password, a quiet TLS handshake failure after a Microsoft-side cipher update, or your server's IP landing on one of Microsoft's internal throttle lists. My approach is systematic: I'll start by testing raw connectivity on ports 587 and 25 using openssl s_client to verify the STARTTLS negotiation, then validate your SASL credentials against Microsoft's endpoint, check SPF/DKIM/DMARC alignment, and query Microsoft SNDS and any relevant blocklists for reputation flags. Once I isolate the break in the chain, I'll apply the minimal targeted fix, send a verified test message to an external inbox, and hand you a concise write-up of exactly what changed and why. I'm available to jump on this right now—let's get your mail flowing again.

@usmanbashir12100

Hi, I understand your Ubuntu VPS suddenly stopped sending mail via Microsoft SMTP despite no visible errors, and you need a fast, precise diagnosis to restore delivery. I’ll methodically trace the full path—connectivity, ports, TLS/STARTTLS, authentication, and any Microsoft-side blocks—to pinpoint the exact cause. I’ll test SMTP handshake and logs in depth, verify credentials and ports (25/587), check for throttling or reputation issues, and apply only the necessary fix. You’ll get working outbound mail confirmed with a test email, plus a clear summary of what was wrong and how it was fixed. Ready to start right away. Usman Bashir

@ayesha86664

Hi there! You are building a working outbound SMTP flow on an Ubuntu VPS and the real challenge is silent failure in TLS or authentication or Microsoft side throttling without clear log errors. In a recent support engagement I restored email delivery for a Linux based system after a similar sudden SMTP breakdown, improving delivery success back to 99% by correcting hidden TLS mismatch and auth handling using Linux mail diagnostics and SMTP tracing. I will run a full path diagnosis from Ubuntu connectivity, port reachability, STARTTLS handshake, credentials validation, DNS checks, and Microsoft throttling reputation signals, then apply the minimal fix and validate with external test delivery. Check our work: https://www.freelancer.com/u/ayesha86664 Is this SMTP using Microsoft 365, Outlook relay, or a dedicated SMTP connector tied to a static VPS IP? I am ready to start, just say the word. Best Regards, Ayesha

@adily1

Hey , I just finished reading the job description and I see you are looking for someone experienced in System Admin, SMTP, Troubleshooting, Ubuntu, DNS, Documentation and Linux. This is something I can do. Please review my profile to confirm that I have great experience working with these tech stacks. While I have few questions: 1. These are all the requirements? If not, Please share more detailed requirements. 2. Do you currently have anything done for the job or it has to be done from scratch? 3. What is the timeline to get this done? Why Choose Me? 1. I have done more than 250 major projects. 2. I have not received a single bad feedback since the last 5-6 years. 3. You will find 5 star feedback on the last 100+ major projects which shows my clients are happy with my work. Timings: 9am - 9pm Eastern Time (I work as a full time freelancer) I will share with you my recent work in the private chat due to privacy concerns! Please start the chat to discuss it further. Regards, Adil.

@haseebsidd07

Hey , I just went through the project description, and I see you are looking for someone experienced in Documentation, Linux, Troubleshooting, DNS, SMTP, Ubuntu and System Admin. It instantly reminded me of a client who faced similar challenges, and I knew I had a tailor-made solution for it. Please review my profile to confirm that I have great experience working with these tech stacks. While I have few questions: • Is there anything else you’d like to add to the project details? • What’s the top hurdle you’re facing with this project? • What is the timeline to get this done? Why Choose Me? 250+ Projects. 5 Years. Zero Misses. My reputation is built on a single metric: Flawless Execution. While others promise quality, my last 100+ consecutive 5-star reviews prove it. I don’t just finish the job; I set the standard. Timings: 9am - 9pm Eastern Time (I work as a full time freelancer) The portfolio here is just the tip of the iceberg. To respect client confidentiality, my recent heavy-hitters aren't public, but I can share them 1-on-1. Click the 'CHAT' button, and I’ll send over the relevant samples immediately for your review. Regards, Abdul Haseeb Siddiqui.

@johnhygh

Hello Sir, With my 9+ years of experience as a Senior Full Stack & DevOps Engineer, I assure you that I possess the breadth and depth of skills necessary to restore Microsoft SMTP on your Ubuntu VPS. My core competencies span across frontend, backend, and cloud infrastructure , a perfect fit for resolving issues at multiple levels. My prowess in Linux and expertise in AWS, GCP, and Azure ensure seamless deployment and scalability; two crucial aspects for a task of this nature. What sets me apart is my systematic approach towards problem-solving. I won't just look at the symptoms but will thoroughly scan the entire path, verifying Ubuntu-side connectivity, TLS/STARTTLS negotiation, authentication credentials, port availability (25/587), and ruling out any behind-the-scenes throttling or reputation blocks that might have disrupted the service. Once the root-cause is located, I will apply the minimal fix needed, document it meticulously - providing a comprehensive summary of diagnostic steps - and confirm success by forwarding a test message to an external mailbox. In projects like these, I aim not only to fix immediate problems but also establish long-term solutions. All my work is built with scalability and maintainability in mind. Should you choose me for this project, I won't just restore your mail service but ensure its optimal performance moving forward. Let's initiate this task right away - I'm available immediately to address this issue! Thanks! John

@dholadipak09

Hi there, Best solution: I’ll trace the full outbound mail path from your Ubuntu VPS to Microsoft SMTP, find the exact failure point, and apply only the minimal fix needed — no random config “experiments” that turn one mail issue into three new hobbies. I can check SMTP connectivity, ports 25/587, DNS resolution, firewall rules, TLS/STARTTLS negotiation, authentication, Postfix/msmtp/mail client config, Microsoft SMTP response behavior, throttling/reputation blocks, and any silent delivery rejection. Once fixed, I’ll confirm by sending a real test email to an external mailbox. I’ll also provide a short summary of the diagnostic steps, root cause, and exact config/command changes made so you can document it properly. Fixed Cost: $30 || Timeline: Same day / immediate start All communication will stay inside Freelancer. Best regards, Dipak