I'm trying to recompile an old Deplhi 5 project but I'm receiving a fatal error saying some of the files are missing.
I've found around 20-25 of the missing components on the Internet, but can't seem to find "LibIntf.pas". Where abouts can I find or download this missing file?
If the compiler tells you you're missing LibIntf.pas, then you're not really missing anything. You're not supposed to have that file. That unit is provided by a design-time package distributed with the IDE. Code that uses that unit can only be used as part of another design-time package. To make it compile, your design-time package should have DesignIDE.dcp in its "requires" list.
Your license forbids you from distributing Delphi's design-time code. The "missing" package serves to enforce that rule. DesignIDE is only usable by other packages, not applications, so if your application tries to use any of its units (like LibIntf or DsgnIntf), then compilation will fail. You need to split the code that needs those units into a separate design-time package.