Blog
How to open files that will not open, and how those formats work, such as winmail.dat and MSG from Outlook, EML email files, HEIC photos from iPhones, VCF contacts, ZIP and LZH archives, and garbled file names.
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How to Convert VCF to CSV for Excel
Convert VCF (vCard) contacts to CSV and open them in Excel. Real conversions of sample files in the iPhone, Android and Google Contacts export formats, what the CSV keeps and drops, keeping the leading zeros on phone numbers, and turning a CSV back into a VCF.
Updated Published
What Is an EML File? What Is Inside, and What to Do When One Won't Open
An EML file is one email saved as text in the internet mail format (RFC 5322 and MIME). A sample file read line by line, which apps save and open .eml, and what to check when one will not open, shows garbled text or has no body.
Updated Published
What Is a VCF File? vCard Versions, Fields and How to Open One
A .vcf file is a vCard: contact cards written as plain text. What the lines mean, how vCard 2.1, 3.0 and 4.0 differ (character sets, quoted-printable), what Apple, Android and Outlook export, and what to do with the file.
Updated Published
What Is winmail.dat? Why Outlook Sends It and What Is Inside
winmail.dat is the TNEF part of an Outlook message that your mail program could not read. Following Microsoft's documentation and the MS-OXTNEF specification: when Outlook sends it, why some recipients see it and others do not, what is inside, and how to open or stop it.
Updated Published
Why File Names in a ZIP Come Out Garbled, and How to Fix Them
Unzip a file from a Japanese colleague and the names read 縺ｯ縺ｾ縺 — or a ZIP made on a Mac garbles on Windows. ZIP never recorded the encoding of names. What each system writes, which tools guess right, and how to re-save the archive so it opens anywhere.
Updated Published
How to Open a .msg File Without Outlook: Three Ways
.msg is Outlook's own format; Gmail, Apple Mail and Thunderbird cannot read it. How to open one in your browser right now, in Outlook, or with a free viewer — and why some open with an empty body.
Updated Published
EML vs MSG: Which to Choose When You Save an Email
EML and MSG compared by what is inside, which apps open them and how each app saves a message — classic Outlook, new Outlook, Outlook on the web, Gmail and Apple Mail — and which to pick when you are not sure.
Updated Published
How to Open EML Files Without Outlook
You can open a .eml file without Outlook. Four ways, with steps, following Microsoft's and Mozilla's own information: in your browser right now, with the new Outlook built into Windows, with Thunderbird, or in a text editor.
Updated Published
How to Transfer Contacts Between Phones
How to move contacts between iPhone and Android (and between phones of the same kind), using Apple's and Google's own instructions: during the new phone's setup (Move to iOS, Android Switch), by syncing a Google Account or iCloud, or with a VCF file.
Updated Published
How to Prevent Winmail.dat: Outlook Settings Guide
Recipients usually get winmail.dat because the sender's Outlook sends in Rich Text. Following Microsoft's documentation: setting the default format to HTML, switching a single message, what to check when it still happens, and how an administrator stops it.
Updated Published
Winmail.dat on iPhone: What to Do When You Receive One
How to get the attachments out of a winmail.dat that arrived in iPhone Mail, in Safari and without installing an app — plus why it happens and what to ask the sender, following Apple's and Microsoft's own explanations.
Updated Published
How to Open winmail.dat on Windows, Mac, iPhone, Android and Gmail
winmail.dat opens in your browser in seconds. What is going on in Windows without Outlook, on a Mac, on iPhone, on Android and in Gmail, and how to get the message and its attachments out in each case.
Updated Published
Writing a TNEF Parser So winmail.dat Never Leaves the Browser
Every winmail.dat converter I could find wanted me to upload the file to their server. So I implemented TNEF from scratch in TypeScript. Here is what is inside the format, and the three details that break naive implementations.
Updated Published
How to Convert HEIC to JPEG for Free, and Whether You Need Software
Wanting a JPEG out of a HEIC often turns into a hunt for free software that dead-ends. The usual recommendations are only free for personal use, and the built-in Windows route has a paid half. Here is what each option really costs, and how to skip installing anything.
Published
HEIC Won't Open on Windows? Three Ways to View iPhone Photos
iPhone photos (.heic) will not open on Windows because Windows ships without a HEIC decoder. Convert them to JPEG in your browser, add the codec extensions to Windows, or have the iPhone hand over JPEG in the first place — compared.
Updated Published
How to Show and Change File Extensions on Windows and Mac
Windows and macOS hide file extensions by default, which is why a file 'with no extension' often has one you cannot see. How to turn them on, how to change one safely, and what changing it does not do.
Published
Why a ZIP File Will Not Open, and How to Fix Each Cause
A ZIP that refuses to open has one of six causes: a truncated download, a password, a split archive, garbled names, a file that is not really a ZIP, or an archiver too old for it. How to tell which, and what to do about each.
Published
Why a CSV Opens Garbled in Excel, and Three Ways to Fix It
A CSV from a Japanese partner opens in Excel as '譁�ｭ怜喧縺�' or '����'. The cause is Excel guessing the encoding. How to convert the file to UTF-8 with BOM in your browser, how to set the encoding in Excel's import, and how to re-save it in Notepad.
Updated Published