# Backtracking Ions - How to?

**URL:** https://forum.spis.org/t/backtracking-ions-how-to/810
**Category:** SPIS
**Created:** [13 November 2020 19:19 UTC](https://forum.spis.org/t/backtracking-ions-how-to/810 "2020-11-13T19:19:47Z")
**Posts on this page:** 3
**Page:** 1

<div class="post-metadata">

### Author: ![SachinReddy7](https://forum.spis.org/letter_avatar_proxy/v4/letter/s/f0a364/32.png) [@SachinReddy7](https://forum.spis.org/u/SachinReddy7)
#### Post date: [13 November 2020 19:19 UTC](https://forum.spis.org/t/backtracking-ions-how-to/810/1 "2020-11-13T19:19:48Z")

</div>

Hi!

New forum looks great. Can you please advise how to set up backtracking ions?

I’ve selected ‘BacktrackingPICCompositeVolDistrib’ in the Global Parameters but it throws an error. Should I be doing any other changes too?

Look to track ions onto an instrument.

Thanks

---

<div class="post-metadata">

### Author: ![SachinReddy7](https://forum.spis.org/letter_avatar_proxy/v4/letter/s/f0a364/32.png) [@SachinReddy7](https://forum.spis.org/u/SachinReddy7)
#### Post date: [13 November 2020 19:24 UTC](https://forum.spis.org/t/backtracking-ions-how-to/810/2 "2020-11-13T19:24:09Z")

</div>

Hi,

Just seen a very old post about backtracking not working ‘with a drifting species’. What does this mean and how can I avoid that?

---

<div class="post-metadata">

### Author: ![SachinReddy7](https://forum.spis.org/letter_avatar_proxy/v4/letter/s/f0a364/32.png) [@SachinReddy7](https://forum.spis.org/u/SachinReddy7)
#### Post date: [13 January 2021 10:06 UTC](https://forum.spis.org/t/backtracking-ions-how-to/810/3 "2021-01-13T10:06:15Z")

</div>

Solved this! Feel free to close it.