Try :
Msg * "insert your message here"
If you are using Windows XP's command.com, this will open a message box.
Opening a new cmd window isn't quite what you were asking for, I gather.
You could also use [VBScript][1], and use this with your .bat file. You would open it from the bat file with this command:
cd C:\"location of vbscript"
What this does is change the directory command.com will search for files from, then on the next line:
"insert name of your vbscript here".vbs
Then you create a new [Notepad][2] document, type in
<script type="text/vbscript">
MsgBox "your text here"
</script>
You would then save this as a .vbs file (by putting ".vbs" at the end of the filename), save as "All Files" in the drop down box below the file name (so it doesn't save as .txt), then click Save!
[1]:
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[2]:
[To see links please register here]