Although 64-bit operating systems and hosts are the norm for years, you might need to use older plug-ins for backward compatibility or a particular VST Instrument which has been discontinued.

32-bit versions of Cubase 4 to Cubase 8.5 and Nuendo 4 to Nuendo 7 came with a VST Bridge meant to make the transition to 64-bit systems easier. But in general, using 32-bit plug-ins in an 64-bit environment can be problematic and cause various problems. 

As of now, you have various options to choose from to deal with this situation:

• Ditch old 32-bit plug-ins and find native 64-bit replacements. This is indeed the easiest solution to manage (system-wise), but replacing several plug-ins in existing projects might be cumbersome.
• Use the internal VST Bridge (only in Cubase 4 to Cubase 8.5 and Nuendo 4 to Nuendo 7). Usually, it will work fine with older Steinberg plug-ins, but the outcome might vary, especially with 3rd party plug-ins.
• Use jBridge. jBridge is an inexpensive third-party solution for bridging. It has several user-selectable options which allow for perfect results with some experimentation and tweaking.
  However, please note that jBridge is not officially supported and we cannot provide support in case jBridge is causing issues.
  jBridge website...
• Use the 32-bit version of Cubase along the current 64-bit installation.
  This option is only recommended, when you don't use sample libraries, orchestral templates or memory intensive VST Instruments. A quick reminder: a 32-bit application can only address 4 GB of RAM on a 64-bit Operating System.
  
  Still, it is a viable (and possibly the best) option to open older projects that were completed with a 32-bit version of Cubase.
  
  On Windows, both versions of Cubase can be installed and used separately.
  
  On Mac OS X, Cubase 6 up to Cubase Pro 8.5 can be used as a 32- or 64-bit application. Instructions on how to switch the bit mode of an application under Mac OS X can be found here.

In all cases mentioned above, a logic and clean folder organization will allow you to reliably bridge where needed and get rid of the additional software when the need for a bridge no longer exists. Read more...