How do I send multi-line messages?
Separate each line of text with <CR><LF> (carriage return/line feed) sequence:
SMTP1.MessageText = "This is " & vbCrLf & "the multi-line" & vbCrLf & "message"

Is it 100% compatible with VB4 (Delphi, Powerbuilder)?
No. In order to use the component in non-VB6 environments please download and run full setup

Control doesn't send MessageText. What to do?
Most likely your e-mail client (older version of Outlook or Notes) expects additional message headers (like "cc" or "bcc") and doesn't parse the message body correctly. Try inserting few blank lines at the beginning of message body:
SMTP1.MessageText = vbCrLf & vbCrLf & "this is the test"

Control can't establish session with SMTP server I've specified.
Lately, due to security restrictions, most of the SMTP servers require authentication before sending (especially relaying) email. If non-authenticated session fails, try to authenticate before sending email. Be sure to select a valid authentication method (the one, recognized by server) and supply login credentials

Component works fine locally. But when I export the program to another machine I get an "object not set" error.
You need to register or install SMTP Component on all machines you are using for developing applications with it. When distributing applications, utilizing SMTP Component, don't forget to include ossmtp.dll in installation package.

When I try to add SMTP Component to my project references, I keep getting a message saying something about name conflicting with existing library.
Most likely you already have a reference to a different library with the same name or older version of SMTP Component. The easiest way to resolve naming conflict would be Registry cleanup: make a search on 'ossmtp' value, delete all keys found, re-register OSSMTP.dll

How do I integrate SMTP Component with MS Exchange.
You can only use SMTP Component to send emails. To get an access to other features of Exchange you need to use MS MAPI controls and/or Exchange object library.

When I ran setup I got 'smtp_component.exe is not a valid Win32 application' message.
Most likely you have incomplete download. For example, download in web browsers sometimes stops without any notification (due to time-outs or network problems). This file should be about 1.5 MB. If the installation package is smaller - try to re-download it

When I tried to register the component using 'regsvr32 ossmtp.dll' I received an error message 'DllRegisterServer in ossmtp.dll failed' (or 'LoadLibrary("ossmtp.dll") Failed')
Most likely you don't have VB runtimes (MSVBVM60.dll, etc.) on your system. To get around this problem you can download and run full setup for SMTP component

Where can I get more information about SMTP?
Read SMTP RFC

Mail server rejects connection attempt from SMTP Component. What's wrong?
- double-check mailserver name (or IP address)
- make sure SMTP server is running on default port (25), if not - you need to set Port property accordingly
- if you are accessing mailserver by FQDN make sure your DNS (or other name-resolution service) is configured properly
- check with network administrator if IP address you are trying to connect from is allowed to access mailserver

How do I send email to multiple recipients?
Use comma-separated list:
SMTP1.SendTo = "orders@mycompany.com, admin@mycompany.com, info@mycompany.com"
or
SMTP1.SendTo = "<orders@mycompany.com>, <admin@mycompany.com>, <info@mycompany.com>"
or
SMTP1.SendTo = """Sales Department"" <orders@mycompany.com>, ""Administrator"" <admin@mycompany.com>, ""Helpdesk"" <info@mycompany.com>"

What's the correct format for Timestamp property?
dd mmm yyyy hh:nn:ss +0000
Where yyyy is 4-digit year, mm - 2-digit month, dd - 2-digit day of month, hh - 2-digit hour, nn - 2-digit minutes, ss - 2-digit, +0000 - time correction between your local time and GMT in +/-hhmm format.
Example: 11 Feb 2005 16:03:05 -0500