Save a log file on each iteration step with parametric sweep.

Hi,

In COMSOL 3.5a I can run parametric sweep over parameter “A” and write a global variable (“B” for instance) into a log file during calculation. With each iteration step I have an updated log file with two columns A and B.

Now I am trying to move to COMSOL 4.2a and to do the same parametric sweep with variable export into one txt file on each iteration step. I tried the following procedure:
1) Add a boundary probe of integral type. This probe value I want to export in to the log file.
2) Add a parametric sweep node under the study 1 node.
3) Add a data node under Export node and set the file name.
4) Add a Export to file node under Study->Job configurations->Parametereic and select Data 1 from Run list.
5) Deselect Clear previous and Add parameters to filename checkboxes.
And I am getting the effort massage: “Error in sweep: could not overwrite existing file.”

Is there probably an easy way to save the log file with “A” and “B” columns on each iteration step? In version 3.5a there is a very simple solution for log file export, see picture 6 in the attachments.

Thank you,
Maxim