MarshallSoft SMTP/POP3/IMAP C/C++ email component library (SEE4C) uses a simple API to send and receive mail, including HTML, MIME Base64 and quoted-printable encoded attachments, from within a C/C++ application.

Features of SEE4C include:
- Send email with inline HTML, GIF, TIF, JPG, BMP and Rich Text attachments.
- Supports ISO-8859 and UTF-8 character encoding.
- Supports CHARSET_WIN_1250.
- Supports email servers that require SSL/TLS.
- Get the number of messages on your email server.
- Get the header lines from any email on your server without reading the entire email.
- Delete any email on the server without downloading the entire email.
- Copy any email on the server without deleting it.
- Receive any email on your server including MIME attachments.
- Download email from your server, automatically decoding MIME attachments.
- Remove contents of incoming attachments.
- Copy email and navigate between IMAP mailboxes.
- Dozens of switches to control how email is sent and received.
- Run up to 32 independent threads concurrently.
- Supports SMTP (ESMTP) and POP3 authentication.
- Supports multiple (simultaneous) connections.
- Supports bulk mail on a distribution list.
- Set return receipt; add TO, CC, BCC recipients.
- Includes multiple C/C++ example programs.
- Does not depend on support libraries (calls to core Windows API functions only).
- Royalty free distribution with your compiled application.
- C source code is available.
- Free technical support and updates for one year.
- Fully functional evaluation version available.
- Supports most C/C++ compilers: Microsoft, Borland, Watcom, LCC, GCC, Digital Mars.
- Supports all versions of 32-bit and 64-bit Visual Studio C/C++ through 2022.
- Includes 32-bit and 64-bit DLL files plus OBJ files for static linking.
- Works with 32-bit and 64-bit Windows XP through Windows 11.