SSIS : his happens when loading a package and the file cannot be opened or loaded correctly into the XML document

I have implemented a SSIS package and created a job to execute the package. I am getting an error

This happens when loading a package and the file cannot be opened or loaded correctly into the XML document. This can be the result of either providing an incorrect file name was specified when calling LoadPackage or the XML file was specified and has an incorrect format. End Error Could not load package "C:\development\CoreAnalytics\Trunk\src\xyz.CoreReference.ETL\xyz.CoreReference.ETL\CoreReferenceETL.dtsx" because of error 0xC0011002. Description: Failed to open package file "C:\development\CoreAnalytics\Trunk\src\xyz.CoreReference.ETL\Willis.CoreReference.ETL\CoreReferenceETL.dtsx" due to error 0x80070003 "The system cannot find the path specified.". This happens when loading a package and the file cannot be opened or loaded correctly into the XML document. This can be the result of either providing an incorrect file name was specified when calling LoadPackage or the XML file was specified and has an incorrect format. Source: {5AF624C1-3061-411D-9E0D-4483A319071E} Started: 14:43:14 Finished: 14:43:14 Elapsed: 0.046 seconds. The package could not be found. The step failed.

1. I have created an credential with the service account
2. Created a proxy associating the service account with the credential
3. Created a job associating with the proxy.

I even tried giving persmission of the path to the service account.

Job step below shows the service account using the proxy and the path of the dtsx specified

The package path is

C:\development\CoreAnalytics\Trunk\src\xyz.CoreReference.ETL\xyz.CoreReference.ETL\CoreReferenceETL.dtsx

I am not sure what I am missing