Are you trying to install it now with winetricks, or manually? If the latter, you are probably not doing all the workarounds winetricks does to get vc2005express to install. One of them is > # Without mfc42.dll, pidgen.dll won't load, and the app claims "A trial edition is alread installed..." The script has additional workarounds, depending on what Wine version is being used. If you really want to install it manually, you should probably read the relevant portion of winetricks to see how it does it.
