How to modify Process Chain to run under BWREMOTE

below is the setup
- a process chain made up of an abap program
+ the program uses 'open dataset' to read the data on a file on the server and eventually to rewrite to a different directory
- when run the process chain get the following message:
"PC could not be scheduled- termination return code 8"

-when I run the abap in the background --> get the following message:
"OPEN_DATASET_no_authority"

- I have ful authorization to run any abap program and have full access to the server file.

- Notes: 947690 & 511475 --> has solution for changing the user id for BW up to and including 4.6C. Our system is 7.0

How can I change the user id in Process Chain so it can run under BWREMOTE and not under my user id.

Issue Description:

Process Chain executes under SY-USERNAME instead of Background user.

Possible Cause:

Flag being marked as 'X' in RSADMIN table for object/field RSPC_EXECUTE_USER when the variant (dynamic always) of the program RSPROCESS is changed.
Once the flag is set for the field mentioned above the processes chain is triggered from the current user ignoring the set background user id.

Solution to reset the flag in RSADMIN table:

Execute the program RSPC_EXECUTE_USER to reset the flag for field RSPC_EXECUTE_USER.
The adverse effect of executing the program can be it will set the flag to 'X' if no such entry exists in the table.
Hence forth user ids can be switched from current user to BC or vice versa.

References

SAPNOTE: 640746


Add the user ID in Process chain --> attributes --> execution user.

1) table RSADMIN does not have an entry for RSPC_EXECUTE_USER
2) In the PC, I am directly calling my abap program instead of calling RSPROCESS