Excel-Export problem to much data?

Hi,

I got problems with Export to Excel, when I run the export Navision crashes after a while (70% or 90%)

I using 2 tables

here the export code

//set filters for table 1
table1.FIND('-');
max := table1.COUNTAPPROX;
REPEAT
   BEGIN
      x := ROUND((i/max)*10000,1);
      Dialog_wait.UPDATE(1, x);
      table2.SETFILTER(...);   
      table2.SETFILTER(...);
      table2.SETFILTER(...);
      IF (table2.FIND('-')) THEN
      BEGIN
         REPEAT
             BEGIN
                 //Do Export to Excel
             END
         UNTIL table2.NEXT <= 0;
      END;
      i := i+1; 
   END
UNTIL table1.NEXT <= 0;

I'm new with developing in Navision.

Where is the problem? memory problem ?

Greetings