File Extension Guide
A PFC file is an email archive created by AOL Desktop software. PFC stands for Personal Filing Cabinet, which is AOL's proprietary format for storing emails, attachments, contacts, and folder organization locally on your computer.
PFC File Quick Facts
AOL Desktop
Created by AOL Software
Email Archive
Messages & Attachments
Folder Structure
Organized Hierarchy
Convertible
Export to PST, PDF, EML
The PFC (Personal Filing Cabinet) file format was developed by America Online (AOL) as part of their desktop email client software. It serves as a local storage container for all email-related data downloaded from AOL's servers, allowing users to access their emails offline and maintain organized archives of their correspondence.
Unlike standard email formats such as EML or MBOX, PFC files use a proprietary binary structure specific to AOL's software. This means they cannot be opened directly with standard email applications like Outlook or Thunderbird - specialized software is required to read, view, or convert the contents.
AOL Personal Filing Cabinet HistoryThe Personal Filing Cabinet has been a core feature of AOL since the early days of dial-up internet. It allowed users to save important emails locally when internet connections were slow and expensive. Even as AOL evolved into a webmail service, the PFC format remained the standard for AOL Desktop users who preferred local email storage.
AOL Personal Filing Cabinet files are comprehensive email archives that store multiple types of data from your AOL account:
Data Included in PFC Files Standard PFC FoldersNote: The exact content depends on what was synchronized from your AOL account and how AOL Desktop was configured.
PFC files have been created by various versions of AOL's desktop software throughout its history:
AOL Desktop Gold
Current version (2016-present)
AOL Desktop 10.x
Modern AOL client
AOL Desktop 9.x
Windows XP/Vista era
AOL 8.0 - 9.0
Early 2000s versions
AOL 5.0 - 7.0
Late 1990s dial-up era
Classic AOL
Original AOL software
PFC File CompatibilityWhile the PFC format has remained largely consistent across AOL versions, some internal structures may vary. Modern PFC viewer and converter tools are designed to handle files from all AOL Desktop versions, ensuring compatibility with both legacy archives from the 1990s and recent backups.
PFC files are stored locally on your computer in the AOL Desktop application data folder. The exact location depends on your Windows version and AOL installation:
// Common PFC File Locations (Windows) Windows 10/11: C:\Users\[Username]\AppData\Local\AOL\ C:\Users\[Username]\Documents\AOL\ Windows 7/8: C:\Users\[Username]\AppData\Local\AOL Desktop\ C:\ProgramData\AOL\ Windows XP (Legacy): C:\Documents and Settings\[Username]\Application Data\AOL\ C:\Program Files\AOL\ // Search for PFC files: Search: *.pfc in Windows Explorer
How to Find Your PFC Files
Open PFC Files Free
*.pfc in the search box
Typical PFC File NamesSince PFC files use a proprietary AOL format, you need specific software to open and read them. Here are your options:
Option 1: Univik PFC Viewer (Free)Univik PFC Viewer is a free Windows application to open and read AOL PFC files without installing AOL Desktop.
Option 2: Univik PFC Converter (For Export)If you need to convert PFC emails to other formats like PST, PDF, or EML, use Univik PFC Converter.
| Program | Platform | Features | Price |
|---|---|---|---|
| Univik PFC Viewer | Windows | View, search, print emails | Free |
| Univik PFC Converter | Windows | Export to PST/PDF/EML/MBOX | $49 |
| AOL Desktop Gold | Windows | Native AOL application | Subscription |
To migrate AOL emails to another email client or create portable backups, you need to convert PFC files to standard formats:
Download Converter
Install Univik PFC Converter on Windows
Open PFC File
Load your AOL archive file
Select Format
Choose PST, PDF, EML, etc.
Export
Convert and save emails
For developers and technical users, here's an overview of the PFC file format structure:
// PFC File Structure (Personal Filing Cabinet) File Header: Magic signature (identifies PFC format) Version information Index table offset Folder count Folder Index: Folder ID Folder name (Inbox, Sent, etc.) Parent folder ID (for subfolders) Message count Message index offset Message Records: Message ID Header fields (From, To, Subject, Date) Body offset and length Attachment count and offsets Flags (read/unread, flagged, etc.) Attachment Data: Filename MIME type Binary content // Note: PFC is a proprietary binary format
The PFC format uses a proprietary binary structure developed by AOL. The exact byte layout is not publicly documented and may vary between AOL software versions.
Standard email applications and text editors cannot open PFC files because they use AOL's proprietary format. Use Univik PFC Viewer (free) to open and read the contents, or PFC Converter to export to standard formats.
PFC file corruption can occur due to incomplete saves, disk errors, or interrupted transfers. Try making a copy of the file before opening. If the file is partially readable, export the accessible emails immediately. For severely corrupted files, professional data recovery may be needed.
Character encoding issues can occur with older PFC files or emails containing international characters. Quality PFC viewers handle multiple encodings automatically. If characters appear garbled, check if your software has encoding options or try a different PFC viewer.
Attachments in PFC files are stored separately from email text. If attachments appear missing, ensure your PFC viewer supports attachment extraction. Use "Save Attachment" or "Extract All" features to save attachments to your computer before opening them.
PFC stands for Personal Filing Cabinet, which is AOL's term for the local email storage system in AOL Desktop software. It's where all your downloaded emails, attachments, and folder organization are stored on your computer.
Most PFC viewers and converters are Windows applications since AOL Desktop was Windows-only. Mac and Linux users can use Windows virtualization (like Parallels, VMware, or Wine) to run Windows PFC software, or convert the files on a Windows computer first.
No, you don't need an active AOL account or subscription. PFC files are local archives stored on your computer. Third-party PFC viewers can open these files without any AOL account or internet connection.
PFC files cannot be directly imported into webmail services. You need to first convert the PFC to a standard format (like EML or MBOX), then use the import features of Gmail or Outlook.com. For Outlook.com, converting to PST and importing via desktop Outlook is often easiest.
Before deleting original PFC files, verify that your converted files contain all emails and attachments correctly. Open and spot-check several emails in the new format. Keep a backup of the original PFC file until you're confident the conversion was successful.
PFC files can grow quite large depending on email volume and attachments. Files ranging from a few MB to several GB are common for long-time AOL users. Older AOL versions had size limits (around 2GB), but modern versions handle larger archives. Very large files may take longer to open and convert.
File Extensions