[Designer/2000] Installation problem!

I have tried to reinstall Form Generator 4.5.9.0.0 from Designer/2000 in Win95! During the installation process, I see that the installer copy all the required files into the designated directories. And then it "Modify the Environment Variable" (the message display on the installer's message box). At this time, a general protection fault appears that states that ORAINST.EXE is conflicted with some dll and the installion is destroyed.

In fact, I have installed the whole software before and there is no such problem appears! The reason for reinstalling this software is that: After I use the Module Data Diagrammer for reverse engineering of a form and then regenerate this form for a number of time, I got a general protection fault of f45g32.exe is conflicted with ioexe.dll. And then I found that there does not exist any Toolbar Icon image on the generated form. So, I tried to reinstall the software, but this time a general protection fault as stated in paragraph one appears.

Are there some location in win95 that stores the Environment Variable of the form generator? This problem only occurs in form generator. For other module such as Report Generator 2.5.????, it seems that there is no problem appears and the oracle installer update the window registry after modifing the Environment Variable of report 2.5. Then it quotes "successful".
Could anyone tell me how to solve this problem such that I needn't reinstall win95 again?

Thanks!

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