My question has been asked by others multiple times in other forums, but, a final answer has not been posted.  And, those forums have so little activity, hopefully enough eyes will see this and provide a definitive answer.  First, the basics:

Windows shared hosting
VBScript file not associated with an ASP file
Plesk Scheduler runs the script as a Task
script sends email via CDOSYS

I found a fairly standardized VBScript using CDOSYS (multiple sites - same basic code that works - here is an example: http://www.lunarforums.com/asp_support/solution_to_using_form_to_send_email_from_asp_page_using_cdosys-t44402.0.html).  I can get it to work when launched from my DSL-connected PC in which my ISP authenticates and I can have it send an email address "to" or "from" any server (i.e. yahoo.com, bellsouth.net).

I have also gotten it to work when launched as a Plesk Scheduler Task in which i use "localhost", but, the "to" address has to be within my domain (i.e. CANNOT be yahoo.com, bellsouth.net), otherwise I get a "551 not our customer" error.  If I try to run the task in which the script tries to authenticate through my domain's email server, the task fails with such severity that I don't even receive "The Plesk Scheduler notification" email.  If I try to run the task in which the script tries to authenticate through my ISP's email server, I get a "transport failed to connect to the server" error.

Is there a way that a VBScript run as a Plesk Scheduler Task can send an email to different (non-LunarPages) domain email address?  Or, is this an issue in which LunarPages does not allow this to happen?

Do you mean kraz.lunarpages.com?

That did not work either.  I tried to authenticate with the same username and password that I use when getting into Plesk.  Just as when I try to get through mail.cometsoftware.com, this failed such that I didn't even receive "The Plesk Scheduler notification" email stating that the task was run.  It would be nice if Scheduler still generated that notification when this failure occurs.

DanielM I appreciate your efforts, but, we can make guesses 24/7.  It seems that I can only run tasks once an hour and only one task per hour, and, I have tried/guessed a number of things the past few days.  So, the point of starting this thread was to try and get a definitive answer.  Since this is not an issue isolated to my account/domain, I think it is appropriate to have this presented publicly in a thread instead of handling it privately through tech support.  And, I don't want this thread to end up like all of the others that I found concerning this issue that is filled with lots of guesses and dies without a resolution.

OK, after trying a few things and talking with tech support, I have a few answers but the main issue is still not resolved.

First, what I have figured out:  The reason why I was not receiving "The Plesk Scheduler notification" email was because I set the "Scheduler notification" to "Send to the default email", which doesn't seem to work.  When I selected "Send to the e-mail I specify", then, I receive the email even with fatal errors in the script or the task parameters.  ***edited for clarification***  This notification email issue was and is totally different from the script, which also sends out an email.  The rest of this post deals with the script and the email that it sends.

Now, for the script which sends out an email, I have tried using "localhost" to send to my Yahoo email account and having my cometsoftware.com email account as the "from" account, and, basically the email disappears to the point that I don't get the email bounced back to my cometsoftware.com account.

Basically, the way that Lunarpages is constructing the email header when I use "localhost" is such that Yahoo thinks it is spam.  I am working with Lunarpages to try to get a copy of that email so that I can contact Yahoo and see what they want to see or not see in the header.  But, otherwise I don't know what to put into the email header to de-spam it.  I believe that this is an email header issue, that is, what is in the header, as opposed to a Windows hosting or VBScript error.  VBScript CDO seems to provide me with all of the header options that I need.

The frustrating thing about this is that, as referenced in the OP, this problem has been brought forward before, but, there doesn't seem to be an answer.  None of the forum threads presents a solution, with some of them suggesting contacting tech support.  I don't think that those threads have specifically mentioned Yahoo as the problem ISP, so, I don't believe that this issue is limited to Yahoo.  I have contacted tech support and gone back and forth with them, and, they don't know what the solution is - other than to contact Yahoo.  It is mindboggling to me that over the years, nobody at Lunarpages and/or in these forums has come up with a solution.

*** edited for clarification***  In a totally unrelated project, within my domain I have a "Contact us" web page that uses a PHP file (and the "mail" function) to generate that email to me, as well as a confirmation email to my "customer".  This works fine and when I test it, I receive emails at my Yahoo account, as well the situation of having the "customer" confirmation email sent to a Yahoo account.  This proves that a domain (specifically mine) within Lunarpages can have a PHP script that sends an email that Yahoo accepts as not spam.  But, this thread is asking how to be able to do that with VBScript and CDO.  So, how is the PHP "mail" function different from the VBScript CDO such that Yahoo accepts the PHP version but not the VBScript CDO version?