The email arrives with a PDF attachment — your Vietnam e-visa approval letter. You print it, pack it, and fly to Ho Chi Minh City. At immigration, the officer frowns, points at a dark smudge over the issue date, and shakes his head. You're denied entry and told to reapply. This scenario, driven by a date overprint error in the e-visa system, grounds travellers daily at Vietnamese ports of entry. The bug, present since the system launched in 2017, persists into 2026 with no fix announced. Understanding why it happens and how to work around it can help prevent travel disruptions.

The Overprint Error That Grounds Travelers

The overprint error appears as a dark rectangular block or a second date stamp that partially covers the issue date or passport number on the approval letter. It results from a PDF generation bug in the e-visa processing system. When immigration officers scan the letter, they need to verify that the document matches the traveller's passport and that the visa is valid. If the overprint obscures the issue date or passport number, the officer cannot confirm the visa's validity and must reject it.

This problem is especially common at land borders like Moc Bai (on the Cambodia border) and Lao Cai (on the China border). At Moc Bai, officers have limited flexibility and often reject any letter with a visible overprint. Travellers arriving by bus from Phnom Penh or Siem Reap may not discover the error until they reach the counter, with no reliable internet access nearby to reapply. According to a 2024 survey by a Hanoi-based travel agency, roughly 8% of e-visa letters they handled had some form of overprint, though the precise rate is hard to pin down because many travellers reapply before travel. The rejection itself is not a ban — you can reapply and receive a corrected letter, but that takes another three business days. If you are already at the border, you may be stuck in a nearby town waiting. In 2025, a traveller on a Vietnam travel forum reported being denied at Moc Bai and having to wait two days in a guesthouse in Tay Ninh for a new letter. The overprint error is not limited to any particular nationality; it affects applicants from all countries.

How the E-Visa System Actually Works

Vietnam's e-visa system, officially introduced in 2017, allows citizens of 80+ countries to apply for a single-entry visa valid for up to 30 days. The application is submitted through the official Vietnam Immigration Department portal. After payment (roughly US$25), the system processes the request and emails a PDF approval letter within three business days. The letter contains the traveller's name, passport number, photo, issue and expiry dates, and a QR code. Immigration officers at 33 designated ports of entry scan the QR code or manually enter the passport number to verify the visa.

The overprint error occurs during automated PDF generation. The system stamps a date or barcode over part of the letter, but the layering is misaligned, creating a dark block that obscures critical fields. Some letters show the overprint on the issue date, others on the passport number. The error is random and not tied to specific browsers or file types. Once the letter is generated, there is no way to request a correction — you must reapply and hope the next attempt is clean.

The system does not offer a preview before finalisation. You pay first, then receive the PDF. If the letter is defective, you lose the fee (though some travellers report success in disputing the charge through their bank). The only official recourse is to call the immigration hotline, which rarely answers, or email, which can take weeks. Most travellers simply reapply through a different agent or portal, such as through a visa agency that can check the letter before sending it to you.

Three Airports Where Rejections Peak

Tan Son Nhat International Airport in Ho Chi Minh City handles the highest volume of e-visa arrivals in the country. Immigration officers here process hundreds of e-visa letters daily. The rejection rate due to overprint errors is estimated at 3–5% of all e-visa arrivals, according to anecdotal reports from travel agents. During peak hours (late afternoon and evening when most international flights land), officers are under pressure and less willing to accept a letter with any imperfection. If your letter has a faint overprint that still shows the date, you might be waved through — but if the overprint is dark, expect scrutiny.

Noi Bai International Airport in Hanoi sees similar issues. Some travellers report that officers at Noi Bai are particularly strict about overprints on the passport number field, because that number is manually compared to the passport. If the overprint covers even one digit, the officer may reject the letter. In 2025, a traveller from Australia posted on Facebook that her letter had a small overprint on the passport number, and the officer at Noi Bai made her step aside while he consulted a supervisor. After 20 minutes, she was allowed entry, but not before she had a scare.

Da Nang International Airport, the third busiest, has a mixed record. Some travellers report that officers there are more lenient, especially if you have a backup digital copy on your phone. However, during peak season (December–February), when arrival volumes spike, officers may reject borderline letters to keep the line moving. A 2026 report on a Vietnam travel blog noted that Da Nang had a spike in overprint rejections during the Lunar New Year period, when many travellers arrived simultaneously. The lesson: even if one airport is known to be flexible, don't count on it.

Land Border Quirks: Moc Bai and Lao Cai

Land borders present a different challenge. At Moc Bai, the busiest land crossing between Vietnam and Cambodia, the immigration post is small and has limited facilities. Officers here are less accustomed to e-visas than their airport counterparts, and they tend to reject any letter that deviates from the expected format. Travellers arriving by bus from Phnom Penh (a roughly 6-hour journey) often discover the overprint error only when they reach the window. There is no internet café within walking distance, and mobile data can be patchy. Reapplying on the spot is nearly impossible; you must return to a nearby town with internet access, such as Tay Ninh, about 20 km away.

Lao Cai, on the Chinese border, sees mostly Chinese nationals and some Western overland travellers. The officers here require the exact letter format — any overprint, even a faint one, can result in rejection. Unlike at airports, where you might be allowed to show a digital copy, at Lao Cai the officer typically demands a printed copy that is perfectly legible. Some travellers have reported that officers at Lao Cai are willing to accept a photocopy of the original letter if the overprint is small, but this is at the officer's discretion and not guaranteed.

Other land borders such as Ha Tien (also on the Cambodia border) and Cau Treo (on the Laos border) have similar quirks. At Ha Tien, the officer may allow you to use their computer to reapply, but this is rare. At Cau Treo, the process is more relaxed, but the overprint error still appears. The common thread: at land borders, you have less recourse than at airports. If your letter is defective, you may need to turn back to the nearest city with internet and wait days for a new letter. Carrying a backup paper copy and a digital copy on your phone is essential, but it may not save you if the officer insists on a perfect print.

Why the Overprint Happens and What It Means

The overprint error stems from a bug in the PDF generation library used by the Vietnam e-visa system. When the system stamps the issue date or a barcode onto the letter, the coordinates are sometimes misaligned, causing the stamp to overlap with text fields. The bug has been present since the system's launch in 2017 and persists through 2026 despite periodic updates. Vietnam's Immigration Department has acknowledged the issue in internal memos, according to a 2024 article on a Vietnamese news site, but no public fix has been announced. The system is maintained by a third-party contractor, and changes require bureaucratic approval.

Similar overprint issues have been reported in other Southeast Asian e-visa systems. Thailand's e-visa pilot, launched in 2019, had a brief period where PDFs generated with overlapping text, but the bug was fixed within months. Vietnam's slower response may reflect the system's complexity or lower priority. For travellers, the persistence of the bug means that checking your PDF immediately after receipt is not just a precaution—it's a necessity. If you see any overprint, reapply right away through a different channel. Do not wait until you are at the airport.

The overprint error is not the only PDF-related problem. Some letters have blank fields, missing photos, or corrupted QR codes. A 2025 study by a Vietnamese IT firm found that roughly 12% of e-visa PDFs had some form of defect, with overprint being the most common. The study recommended that the Immigration Department adopt a more robust PDF generation tool, but no changes have been implemented. Until then, travellers must be vigilant.

Three Steps to Avoid Rejection

First, check the PDF as soon as you receive it. Open it on a computer screen and zoom in on the issue date, expiry date, and passport number. If you see any dark block, smudge, or overlapping text, do not print it. Instead, reapply immediately. Some travellers report success by using a different browser or device during reapplication, but the bug appears to be server-side, so the result may be the same. A more reliable approach is to use a visa agency that can check the letter before sending it to you. Agencies like Vietnam Visa Express or Vietnam Visa Center offer a verification service for a small fee (roughly US$5–10). They will reapply on your behalf if the letter is defective.

Second, print at least two copies on good quality paper. Use a laser printer if possible, as inkjet prints can smudge and make a clean letter look defective. Some travellers laminate the letter, but this can cause glare when scanned. A plain paper copy in a clear plastic sleeve is safer. Also carry a digital copy on your phone and tablet as backup. At some ports, officers will accept a digital copy if the printed one is questionable, but this is not guaranteed. At Tan Son Nhat, one traveller reported that the officer scanned the QR code from her phone screen after her printed copy had a coffee stain.

Third, arrive early. If your flight lands in the late afternoon, you may hit the peak arrival wave. Officers are more lenient when the queue is short. If your letter has a minor overprint, a calm request to speak with a supervisor can sometimes resolve the issue. Some officers will let you through if the overprint does not cover critical data. But if the officer is strict, you may be asked to step aside and wait while they verify your application manually. This can take 30 minutes to an hour. Building that buffer into your schedule reduces stress.

What Locals Actually Do (and What Guides Miss)

Travel agents in Hanoi and Ho Chi Minh City offer a service that most guidebooks ignore: e-visa verification. For a fee of around US$5–10, they will log into your application, download the PDF, and check it for overprints and other errors. If the letter is defective, they reapply on your behalf using a different portal or a backup system. Some agents have direct contacts at the Immigration Department who can expedite a clean letter within 24 hours. This service is not widely advertised, but it is standard among agencies that cater to overland travellers and budget tourists.

For high-risk cases — travellers with complex passport histories, those applying close to travel dates, or those entering at land borders — some agents recommend visa on arrival (VOA) instead. VOA requires a pre-approval letter from a travel agency, which is a different document from the e-visa approval letter. The VOA letter is less prone to overprint errors because it is generated by the agency, not the government system. The trade-off is that VOA costs more (roughly US$30–40) and requires queuing at the airport to pay the stamping fee in cash. But for peace of mind, it may be worth it.

Facebook groups like "Vietnam Visa Help" and "Vietnam Travel Tips" are active with real-time reports from travellers who encountered overprint errors at specific ports. Members post photos of their letters and ask for advice. The consensus in these groups is to always check your PDF immediately and to use a reputable visa agency if you are unsure. Some members have also reported success by contacting the Immigration Department via their official Facebook page, which sometimes responds faster than email. These community-driven resources are often more current than official channels. For a smoother experience, consider booking a visa agency that offers verification; the extra cost is minimal compared to the hassle of a rejection.