SUMMARY
An Installation Guide (Installation Guide.htm) is provided in the root directory of the BizTalk CD. The Installation Guide contains a section called "Silent Installation" that explains how to perform a silent install. Step 3 provides the following instructions:
msiexec /I "\\server\folder\Microsoft BizTalk Server.msi"
/qb /Lv*"C:\Temp\install.log" INSTALLLEVEL=200
ALLUSERS=1
PIDKEY="your 25-character product key (without dashes)"
DSNCONFIG="C:\Temp\BizTalkInstall.ini"
If you copy and paste this code into a command window (ensure that the paths to the .msi, .log, and .ini files are correct) and run the code, the following dialog box appears: