DATASET_NOT_OPEN

We have a scheduled Job that runs an ABAP Program to pull some data from an external R3 system and put the data as a file on our PI system.

The target Destination of the file is mentioned as a path in the variant of the program.

Today it gave the following exception while running: CX_SY_FILE_OPEN_MODE with the runtime error being DATASET_NOT_OPEN. This is only noticed while running One of the variants. The other variants are working fine. All variants have the same target host location.

Any Suggestions???