Why does DLP Enforce Server time-out when accessing WMI

Why does DLP Enforce Server time-out when accessing WMI, thereby unloading the lookup plugin? No matter what I set the time-out value to, the lookup plugin unloads and gives an error.

The following script will cause the plugin to unload and create error:

import sys, subprocess, socket, string
import wmi, win32api, win32con

for item in sys.argv:
    s = item
    if "sender-ip=" in s: 
        a = s.replace(',', '')
        
userIP = a.strip('sender-ip=')
userloggedon = ""
    
# perform system lookup of IP address
userIP = "\\\\" + userIP
    
pst = subprocess.Popen(
        ["D:\pstools\psloggedon.exe", "-l", "-x",  userIP],
        stdout = subprocess.PIPE,
        stderr = subprocess.PIPE
    )
 
out, error = pst.communicate()
    
    
userLoggedOn = out.split('\n')[1].strip()
print 'userId={}'.format(userLoggedOn)

But if I rewrite the script such that it doesn't execute pst=subprocess.Popen(...., then the script executes without error

import sys, subprocess, socket, string
import wmi, win32api, win32con

for item in sys.argv:
    s = item
    if "sender-ip=" in s: 
        a = s.replace(',', '')
        
userIP = a.strip('sender-ip=')
userloggedon = ""
    
# perform system lookup of IP address
userIP = "\\\\" + userIP
    

    
    
userLoggedOn = "DOMAIN\user"
print 'userId={}'.format(userLoggedOn)

Our environment is configured as follows:

1. Script is in D:\SymantecDLP\Protect\plugins
2. DLP Enforce Server is running on Windows Server 2008 where UAC is disabled
3. "protect" account on DLP Enforce Server is local admin

How do I troubleshoot this? Contacting Professional Services is NOT an option for us. 

Thank you.