Blat 2.7.5 cannot insert text

I'm running Blat on my computer to test and then roll it out to some users in our network.

First off, I have a simple batch file that zipped several files (for backup purpose) and then send an e-mail notification to several people saying the backup was completed.  This is a sample of the blat command line.
1. I first install Blat.  c:\blat -install <IP addr of internal SMTP server> <e-mail addr of sender>
The install went through no error.
2. Then inside the batch file, I have blat run. C:\blat\blat textfile.txt -t "email_1@dot.com, email2@dot.com, email3@dot.com" -s "Backup completed"

When the batch file ran, I received the error msg: "Unknown error code 2 when trying to open textfile.txt".  I didn't receive any e-mail notificaitons from blat.

What is wrong with the syntax?  Textfile.txt is in the same directory as Blat.exe (C:\blat)