Nikon Capture NX 2.2.4 cannot save file.

Did as you suggested, still had problems. Then I took a look at NX2. Uninstalled, then installed NX2 v 2.3.4 x64. Both the program and plug-in installed in 64-bit mode. Thanks for the info.

Perhaps the OP will want to go ahead and install NX2 version 2.3.4 x64, rather than keeping it at version 2.2.4.