Let us be blunt: The is a security liability.
Modern Windows uses "Side-by-Side" (SxS) assemblies to allow multiple versions of the same DLL to exist simultaneously. However, VC6 predates this technology. It was a "global" installation, usually dumping files directly into C:\Windows\System32 . This creates conflicts if a newer application overwrites the VC6 files with incompatible versions. microsoft visual c 6.0 redistributable
Remove the embedded manifest from the legacy executable using a resource editor or use the mt.exe tool: mt -inputresource:yourapp.exe;#1 -remove_manifest . Let us be blunt: The is a security liability