An error occurred while checking for application updates.

This is the most common error encountered during a Just in Time Upgrade and can be displayed for a number of reasons.
The first step to determining the cause is to examine the X_ERR.LOG file on both the JIT Application Server and the Client PC.
In most cases this will point out exactly what the issue is, and corrections can be made to resolve the issue.
Refer to the following more specific issues for more information.

Cannot connect to JIT Application Server.

There are a few different areas to check in this case:
1. Check that the User (ASUS) and Password (ASPW) supplied are correct or Trusted Connection is selected (ASTC).
Ensure the User is valid as a login to the JIT Application Server.
Double-check the User and Password was entered correctly.
Check the User and Password values in the application start file on the Client PC.
 
2. Check the Host Route entry exists and is correct in the lroute.dat file using the LANSA Communications Administrator.
Ensure LANSA Communications has been deployed to the Client PC.
An appropriate entry should exist in the lroute.dat file on the Client PC.  Check the LU name, Qualified Name and port number are correct.
Check the listener is started on the JIT Application Server and listening on correct port.
 
3. Check the network configuration
Verify the IP Address being used
Correct any network errors.

Errors encountered during the update checking.

1. Check the JIT Application Server has a valid SuperServer license installed
2. Check the directory structure
The directory structure in the x_apps directory on the JIT Application Server is very important and should not be modified.
The x_apps\<application name> folder should include the MSI or MSP files associated with the application Versions and Patches to be deployed.

New Package not downloaded as expected.

1. Use the Windows Control Panel Add or Remove Programs to determine the Application installed. Compare that with the MSI or MSP files available on the Application Server.