This is a VERY strange error, but is a big problem.
I use I:\ as my windows boot drive not C:\. So when I go to File->Open Data Folder, the program opens the installation folder in I:\Apps\MetaTrader 4 IC Markets, not the User\AppData\Roaming\... folder.
This also means that custom compiled code in the installation folder\MQL4\Indicators folder works. Developing code and installing on my machine is completely different than on a normal user's machine.
I am using build 604.
Welcome to mql4.com forum,
It doesn't seems strange to me, your "old" build was already installed in this folder ? Which Windows are you using ?