Sure, upgrade to a newer version of Quicken. It's not just as simple as pasting in a specific file because all too often companies will distribute their own custom versions of DLL files like that. So unless you have the exact one needed by that particular program, you can run into problems like you did.
Plus, depending on how the program was written, it may simply not be possible to make it work on Windows 8. It's a roughly 10 year old piece of software, so if Intuit strayed outside the bounds of the Windows API, which is very likely if TurboTax is anything to go by, that means all bets are off as to how long it will work with future versions of Windows. Some security patch or Microsoft simply starting to enforce a rule that has been in place for several years, could cause the program to break irreparably.
The other reason you upgrade periodically is that given the program version you're using is ~10 years old, there's a decent chance newer versions of Quicken won't even be able to import it. The general assumption being that people have upgraded somewhere along the way. Those people who didn't are stuck trying to figure out how to deal with this old format file that can't be used with the current version.
Luddite and/or laggard tendencies do not behoove you in the technology world. You need to be flexible and able to adapt to changes quickly else you get left behind and have to deal with situations exactly like you're facing now when you can't hold out any longer.
I was having trouble installing Quicken 2004 because the file :- MFC70.dll was missing well I found a site and downloaded and pasted the file into the program, all well and good I managed to restore my saved file and the proceeded to bring everything up to date which took some time as it was some time ago since my HD failed to make sure I stayed up to date I proceeded to back it up and the whole program froze the only way I could get out of it was CAD so I deleted the program reinstalled it (and the missing file) then did a trial back up the same thing happened any ideas out there?

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