ok iv noticed a few poeple have been haveing this problem so i decided to share my knowledge. This method was told to me by a mill seller about 2 years ago.
ok here goes
load up a world log in
load up another world
open the "run" option on ur start menu
"c:\windows\.file_store_32" type this in
delete a file called UID.dat
and hey presto u can now log in on the second world you loaded up
ps every time you want to multi log you will have to delete the file again because it comes back i dunno how or why this works
but it does lol
hope this helps

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