When doing a jackknife with Zmapqtl, the user should check that the file ending in the letter i is truely the last version of the interim jackknife file. Zmapqtl switches between a file ending in i and another ending in j, so check both and move the j file onto the i file if required.
If you set the significance threshold too high, then Eqtl may find no QTL in the qtlcart.z output. If this is the case, then Eqtl will crash.