Possible Reasons:

1. Data collection script may be running too slow and could have timed out due to some network issues in Windows.
2. Target remote server did not respond because it was hung or performing some resource intensive operation.
3. WMI classes got corrupted in the target server.
4. Recent Firewall / AV upgrade / policy changes are blocking traffic between Applications Manager and the target server.

Troubleshooting :

Customers using build 15160 and above:

1. Navigate to Admin > Tools > Self Help Tools.
   
2. Choose the required host and monitor type.
   
3. Click on the Execute button to run the script.
   
4. View the report generated and check the WMI Tool overall execution time.
   
5. If it is very high, refer the fix suggested in this solution.

Customers using build below 15160:

1. To verify the error, please run the data collection script in both the Applications Manager installed server and the actual server to check the time taken for the WMI query execution.

1. Open command prompt as Admin User.
   
2. Go to the path <APM_HOME>\working\conf\application\scripts in the command line and execute the following:
   

Fix:

1. In the target server, login using same credentials provided in Applications Manage and test if the WMI query execution is slow.
   
   1. Run WBEMTEST, connect the namespace root\cimv2
      
   2. Click on query and enter query as "Select * from Win32_ComputerSystem"
   3. Note down the number of seconds the query takes to execute.
      
   If this also takes time, WMI could be corrupted.
   
   Kindly perform the WMI reconstruction operation based on the suggestion given by Microsoft in the below URL:
   
   https://techcommunity.microsoft.com/t5/ask-the-performance-team/wmi-repository-corruption-or-not/ba-p/375484
   
   
2. Test if the remote basic WMI query from Applications Manager server is slow by using the same account used for monitoring.
   
   1. Run WBEMTEST, connect the namespace \\machinename\root\cimv2
   2. Provide the username and password for the remote machine
   3. Click on query and enter query as "Select * from Win32_ComputerSystem"
   4. Note down the number of seconds the query takes to execute.
   If this query takes a longer time to run, the problem might be in the network between Applications Manager server and the target monitored server. So check for any changes in AV / Firewall settings.
   
   
   
3. If the server is expected to respond slow, increase the script timeout to avoid the Data Collection Timeout issue. (this is generally not recommended as this increases the time taken to fetch metrics and can cause slowness in data collection).
   

   Here are the troubleshooting steps to increase the timeout:

   1. Navigate to Windows->Monitor Details Page->Snapshot View->Edit Monitor.
   2. Add 300 more seconds to the Timeout value.
   3. Now poll the problematic monitor and check if the issue persists.
      
   
   
4. Check for network issues. Check the Receive Side Scaling and the TCP Chimney registry settings. If you have enabled TCP Chimney along with RSS setting, WMI may fail. 
   

If still problem persists, share error monitor page screenshot, edit monitor page screenshot, self help tool output or script output and support information file to appmanager-support@manageengine.com.