Check for Basic Mistakes  

Since the upgrade configuration cannot be compiled, it is possible for the user to make simple mistakes while creating the upgrade.  Hence, it is important to review all commands, names of files and target directory paths before sending the upgrade.  

Furthermore, you can make a check on the following: 

·        Check if you are trying to use the same machine to send and receive upgrades. This will not work unless you adopt a workaround. For more information, see the SAP Note 373331.

·        Do not check the 'Offline' upgrade flag if you want to deploy upgrades manually. An upgrade that is marked "Offline" can be started only by an initiator upgrade.

·        Check if the upgrade fails due to an earlier upgrade that may have been faulty. If an upgrade fails, then it will attempt the process again. This recurrs three times, after which the upgrade BDoc is removed from the queue. So if you try to stop the execution of the ClientUpgradeTarget.exe and send a new upgrade again, the older upgrade gets invoked when you run ConnTrans. This is because it is is still in the queue and the registry.