opera portable process would not exit

I don't know something wrong where , when I run opera portable(Vol.11.60)on portabbles.com starter ,the opera portable process would not exit after I closed it, but when I run opera portable directly , the process would exit without anything wrong.
I put opera directly(not portable edition) into PortableApps folder , and run it on starter , the same would happen . So I think there is something work wrongly between portable.com starter and opera.