Trojan in Firefox [SOLVED]

[JW01]

I have run a full scan using McAfee twice in the past two days and each time it has encountered trojan JS/Redirector.dg in C:\Sandbox\User\DefaultBox\user\current\AppData\Local\Mozilla\Firefox\Profiles\ou4hy8lv.default\cache2\entries\499F9EB362AF6C63CAAF9A00948472B0, which it has cleared.
I have only just started using Sandboxie and I start Firefox sandboxed, so I don't understand how a trojan could have escaped.
Can anybody explain what I am probably doing wrong?
Thanks for any help.

[Barb@Invincea]

Hello JW01,

C:\Sandbox\User\DefaultBox\user\current\AppData\Local\Mozilla\Firefox\Profiles\ou4hy8lv.default\cache2\entries\499F9EB362AF6C63CAAF9A00948472B0

That location is inside your Sandbox, it has not escaped, it is contained as expected. If you delete your Sandbox contents, it will delete that entry as well.

If you have given full access to the Firefox profile or cookies/history, then they can modify your host:
https://www.sandboxie.com/index.php?FirefoxTips

Regards,
Barb.-

[JW01]

Emptied contents, reran McAfee scan, all gone!
Many thanks for your help.