This is the error I keep getting: "An error occurred while copying file inetcorp.iem. Cannot copy file to destination directory."
Had the same problem on WinXP Home Russian SP3 during ie6 to ie8 upgrade: "Не удается скопировать inetcorp.iem".
Googled this article, opened Start - Run - ie8.log
139.109: Скопирован файл: c:\WINDOWS\inf\IEM\0419\inetcorp.iem - was the last entry.
I went to the folder C:\WINDOWS\INF and found a file named IEM. The installer most likely failed to create the folder IEM and showed the error.
So I simply deleted the IEM file, and clicked Retry on the error window. All OK.
Did this solve your problem?
Sorry this didn't help.