Problem with File.Exists() method.

[Tim Richardson]

I am attempting to copy some files from one machine to
another. I am having difficulty with the File.Exists()
in the code below. The program enumerates the files in a
directory, checks them against a cuttoff DateTime, and
copies them if thet do not already exist. All progress
is written to a log (a snippet is included below the
code). The File.Exists() method returns false even when
the file does in fact exist. Have I coded this
incorrectly?

P.S. This code seems to work on my XP test box, but when
I copy it to the production machine running Windows 2000
server, it fails.
CODE SNIPPET:

for(int i=0; i < sourceFileArray .Length; i++)
{
if(DateTime.Com pare(sourceFile Array[i].CreationTime,
cutoffTime) < 0)
{
string destinationFile Path = destinationDir. FullName
+ @"\" + sourceFileArray[i].Name;

this.targetShip pingLine.WriteT oLog
("DEBUG",destin ationFilePath, Convert.ToStrin g(File.Exists
(destinationFil ePath)));

if(!File.Exists (destinationFil ePath))
{
try
{
sourceFileArray[i].CopyTo(destina tionFilePath);
this.targetShip pingLine.WriteT oLog("LOGCOPY",
sourceFileArray[i].Name, "Sucessfull y copied log.");
}
catch (System.Excepti on e)
{
this.targetShip pingLine.WriteT oLog
(true, "LOGCOPY", sourceFileArray[i].Name, e.Message);
}
}
}
}

LOG SNIPPET:

DEBUG <some filepath> 10/20/2003 1:55:53 PM
False
ERROR LOGCOPY <some filepath> 10/20/2003 1:55:53 PM
The file <some filepath> already exists.