<html><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; ">Hi Berk,<div>thanks for your answer. I've checked the charge groups and every thing seems to be ok (no single groups...). Actually I'm using 3.2.1 version, but it doesn't seem to be depending on that.</div><div>What could I check?</div><div><br></div><div>Fabio</div><div><br><div><html>On May 8, 2008, at 4:00 PM, <a href="mailto:gmx-users-request@gromacs.org">gmx-users-request@gromacs.org</a> wrote:</html><br class="Apple-interchange-newline"><blockquote type="cite"><span class="Apple-style-span" style="border-collapse: separate; color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; orphans: 2; text-align: auto; text-indent: 0px; text-transform: none; white-space: normal; widows: 2; word-spacing: 0px; -webkit-border-horizontal-spacing: 0px; -webkit-border-vertical-spacing: 0px; -webkit-text-decorations-in-effect: none; -webkit-text-size-adjust: auto; -webkit-text-stroke-width: 0; ">------------------------------<br><br>Message: 3<br>Date: Thu, 8 May 2008 15:21:16 +0200<br>From: Berk Hess <<a href="mailto:gmx3@hotmail.com">gmx3@hotmail.com</a>><br>Subject: RE: [gmx-users] crash nsgrid.c<br>To: Discussion list for GROMACS users <<a href="mailto:gmx-users@gromacs.org">gmx-users@gromacs.org</a>><br>Message-ID: <<a href="mailto:BLU134-W186D4AB05B3933895E45F18ED00@phx.gbl">BLU134-W186D4AB05B3933895E45F18ED00@phx.gbl</a>><br>Content-Type: text/plain; charset="iso-8859-1"<br><br>Hi,There can be many reasons for such problems.I assume you use solvent.One option is that you could have made your whole proteina single charge group. grompp in Gromacs 3.3.3 checks for this,but older versions do not.Berk</span></blockquote></div><br></div></body></html>