v4.20 vista installation problem

[Mij]

I'm so glad I found this thread as I've been having this exact problem.....
After looking through the previous posts, I found two ways to fix the problem.
1. Simply delete the .ini file in Program Folders\Irfanview
or 2. By editing the 2nd line to
INI_Folder=%APPDATA%\Roaming\IrfanView
Cheers!

I am pleased your problem is solved mad_quantum but I would not recommend either of your solutions to anyone.

If you delete the .ini file in Program Folders\IrfanView another will be created as a Vista Compatibility file probably in C:\Users\[Your user name]\Local\Virtual Store\Program Files\Irfanview. That is what Vista does when you attempt to write without the correct authority to any file in the protected "Program Files" area.
There may be no problem but users have had difficulties with it in the past which is why that special 2 line redirection .ini file that you describe was put there. That will cause the working i_view32.ini file to be created automatically in the correct part of the Appdata folder for the current user to access.
I cannot see how adding "\Roaming" into the text will solve anything. If it is appropriate to use the \Roaming subfolder then Vista will automatically include it when it expands the %APPDATA% environment variable.

[Mij]

It has just occurred to me to ask if perhaps you are working on a network where you are not the administrator? The whole point of the %APPDATA% variable is that it should point to somewhere that the current user does have permission to save his application data but it would be quite easy for a network administrator who does not know what he is doing to set up a system policy to thwart that.