please specify your software version. I assume it is OpenLAB ChemStation? Unfortunatelly, there is no way how to do it automatically for all samples in ChemStation.
Thanks majkee. Yes it is OpenLab ChemStation.
You can achieve this by loading multiple runs and applying the blank.
1) place a check mark in the overlay of the sequence window. Then right click and select "Load signals / the signal you want"
2) From the file menu select "Subtract Blank Run..." It will apply the blank subtraction to each file.
3) If you wish you can then save the resulting subtracting but using the "Export File/ AIA..."