Peer inside the hash reference via Data::Dumper ...

use Data::Dumper;
{
  local $Data::Dumper::Indent = 1;
  local $Data::Dumper::Deepcopy = 1;
  local $Data::Dumper::Sortkeys = 1;

  warn Dumper( $RS_UsersToRemind->Fields( 'idEnrollee' ) );
}
[download]

hm all I get with that is var1 is undefined. maybe I put in the wrong place or something?

####
#### Filename: reminder.pl
#### Version: .1.0
#### Written
#### Written Date: 03/22/06
#### Last Change 
#### Comments: 03/22/06 This had to be completly re-written 
#### Comments: 03/27/06 Fixed logging to include date/timestamp and se
+perate days with newlines
#### Comments: 10/28/08 Updated From Email address to generic address 
+to exchange changes,added ### myself for debugging purposes.
#### 12/19/06 Removed all references to old IDs
####

#### Modules ####
    use OLE;
    use Mail::Sender;
    use Data::Dumper;

#### lnitialization of Global Variables & Arrays ####
    my $debug =0;
    my $t = time;
    (my $sec, my $min, my $hour, my $mday, my $mon, my $year, my $wday
+, my $yday, my $isdst)=localtime($t);
    $year = $year + "1900";
####    my $SQLServer="servername";
    
    my $DB = "$dbname";
###    changed for security.. 
    my $SQLUname = "username";
    my $SQLpass="pass";

#### Get List of Users to Remind ####
    open(LOGFILE,">>Reminder.log");
    print LOGFILE "\n\n".localtime($t)."\n";
    
    my $Conn = CreateObject OLE "ADODB.Connection";
    $Conn->Open("PROVIDER=SQLOLEDB;DATA SOURCE=$SQLServer;UID=$SQLUnam
+e;PWD=$SQLpass;DATABASE=$DB");
    my $RS_UsersToRemind = CreateObject OLE "ADODB.Recordset";
    my $RS_UserUpdate = CreateObject OLE "ADODB.Recordset";
    
    if ($Conn)
    {
        my $SQL_UsersToRemind = "
            SELECT ClassSchedule.EventDate AS EventDate, 
                DATEDIFF(dd, { fn NOW() }, ClassSchedule.EventDate) AS
+ Until, 
                DATEDIFF(dd, ClassRoster.Enrolled, ClassSchedule.Event
+Date) AS Since, 
                Classes.Duration AS Duration, 
                Classes.Topic AS Topic, 
                Classes.Description AS Description, 
                ClassLocation.Location AS Location, 
                ClassLocation.Address AS Address, 
                ClassLocation.Directions AS Directions, 
                ClassLocation.Map AS Map, 
                ClassRoster.idEnrollee AS idEnrollee,
                ClassRoster.System AS System,
                ClassRoster.Account AS Account,
                ClassRoster.PublicID AS PublicID,
                ClassRoster.Name AS Name,
                ClassRoster.Email AS emailAddress
            FROM ClassSchedule 
                INNER JOIN
                    Classes ON ClassSchedule.id_Class = Classes.idClas
+s 
                INNER JOIN
                    ClassRoster ON ClassSchedule.idEvent = ClassRoster
+.id_Event
                INNER JOIN
                    ClassLocation ON ClassSchedule.id_Location = Class
+Location.idLocation
                WHERE (ClassSchedule.EventDate > { fn NOW() }) AND 
                    (ClassRoster.Cancelled IS NULL) AND 
                    (ClassRoster.Reminded IS NULL) AND 
                    (DATEDIFF(dd, ClassRoster.Enrolled, ClassSchedule.
+EventDate) > 7) AND 
                    (NOT (DATEPART(dw, { fn NOW() }) IN (1, 7))) AND 
                    (DATEDIFF(dd, { fn NOW() }, ClassSchedule.EventDat
+e) < 7)";
                    
        $RS_UsersToRemind->Open($SQL_UsersToRemind, $Conn);
         local $Data::Dumper::Indent = 1;
  local $Data::Dumper::Deepcopy = 1;
  local $Data::Dumper::Sortkeys = 1;

  warn Dumper( $RS_UsersToRemind->Fields( 'idEnrollee' ));

        if ($RS_UsersToRemind)
        {
            while(!$RS_UsersToRemind->EOF())
            {
                print "$RS_UsersToRemind";

                my $SQL_UserUpdate = "update ClassRoster set Reminded=
+{ fn NOW() } where idEnrollee = '".$RS_UsersToRemind->Fields('idEnrol
+lee')->{Value}."';";
                my $sender = new Mail::Sender
                {
                    smtp => 'vaexch001.firstamericanmls.com', 
                    from => 'training@marketlinx.com'
                };
                (
                    ref ($sender->MailMsg( 
                            {
                        to => "".$RS_UsersToRemind->Fields('emailAddre
+ss')->{Value}."",
                                bcc => "training\@marketlinx.com, fran
+cisco.oquendo\@firstamericanmls.com,medwards\@marketlinx.com",
                                subject => "REMINDER: ".$RS_UsersToRem
+ind->Fields('Topic')->{Value}."",
                                msg => 
"This message is to remind you that you are registered to attend ".$RS
+_UsersToRemind->Fields('Topic')->{Value}.". 

Date/Time: ".$RS_UsersToRemind->Fields('EventDate')->{Value}."

Location: ".$RS_UsersToRemind->Fields('Location')->{Value}."

Address : ".$RS_UsersToRemind->Fields('Address')->{Value}."

Seating is limited, so if you no longer plan to attend the class, plea
+se cancel on www.MLXhelp.com",
                                auth => 'LOGIN',
                                authid => 'FAMLS\\foquendo',
                                authpwd => '',
                            })
                        ) and print LOGFILE "Mail sent to ".$RS_UsersT
+oRemind->Fields('emailAddress')->{Value}." OK.\n" ) or die "$Mail::Se
+nder::Error\n";
                $Conn->Execute($SQL_UserUpdate);    
                print LOGFILE "Updated ".$RS_UsersToRemind->Fields('Sy
+stem')->{Value}.",".$RS_UsersToRemind->Fields('Account')->{Value}.","
+.$RS_UsersToRemind->Fields('PublicID')->{Value}.",".$RS_UsersToRemind
+->Fields('Name')->{Value}.",".$RS_UsersToRemind->Fields('emailAddress
+')->{Value}." for ".$RS_UsersToRemind->Fields('EventDate')->{Value}."
+,".$RS_UsersToRemind->Fields('Topic')->{Value}.",".$RS_UsersToRemind-
+>Fields('Location')->{Value}." OK.\n" or die "Unable to Update\n";
                $RS_UsersToRemind->MoveNext();
            }
        $RS_UsersToRemind->Close();
        }
    $Conn->Close;
    close(LOGFILE);
    }
[download]

(Note that I put '{' & '}' around local ... warn Dumper ... to limit the scope of changes to variables in Data::Dumper package. (So much for avoiding OO interface. ** sigh ** ))

Instead of dumping just the idEnrollee field, you could try dumping $RS_UsersToRemind: if everything else is there besides idEnrollee then surely you might have problem|mismatch in your SQL or the table. Somebody familiar with your database and/or associated driver would be able to provide you with a better clue.