I'm using Listx to grab affiliate ID's out of the querystring, for every page on our site. The query variable name is 'ref'.

The following works fine the first time, however on subsequent page loads, the cookie is overwritten with a blank value.

I'm doing a check for the cookies existence in here so I don't follow why it's writing the cookie more than once, can someone help?:

1. If [Userid,System] = -1
2. If [FORMAT,[refid,q],{LENGTH}]<1
3. Assignment: Assign <Session> variable 'sRefID' to '[ref,q]'.
4. Assignment: Assign <Cookie> variable 'refid' to '[sRefID,Session]'.

Oops, 2. If [FORMAT,[refid,q],{LENGTH}]<1 should be:

2. If [FORMAT,[refid,q],{LENGTH}]>1

Still, same problem - it's apparently writing the cookie on every page load, and obviuosly without the query variable present it's going to be making a blank cookie. What am I missing?

You do know that on step 3 your are referring to a different query string parameter?
Thanks,

Oops yes that's definitely a mistake but it was just relating to the session variable.

I believe I have discovered the problem: I have this Listx in a module that has "Display Module On All Pages?" set on in the module settings.

Once I turned this off and then on again, the new way I have the Listx configured seemed to kick in on all the other pages in the site.

Yes, doing this can cause erratic behaviour in ListX. The configuration are tied to a module, so if you make a change in one location, it will change it for all the modules on the site. Just something to keep in mind.
Thanks,

test