Change a user's style / template using php

[30et]

Hi there

I want to write a page that changes the template a user is using, and then redirects them to another url (outside of vbulletin) but in the same domain so that when they return to vbulletin they get the new template.

I thought I could do this on a php page - just change the template setting and then redirect their browser. But I can't figure out how or where the template setting for a user is stored.

I see that there is a cookie called 'bbstyleid' which has the template's style id.
And in the database there is a field in the 'user' table which is 'styleid'.
And also there is another table called 'session' which has a field named 'styleid'.

I have tried to modify the fields in the tables but they don't seem to take effect. And I have also tried changing the cookie value using

setcookie("bbstyleid", "12345");

But it doesn't seem to change?

Does anyone have a suggestion?

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