Why RPM 4.5 is not supported on Windows 7

We get the question from time to time about the previous version of our RPM Remote Print Manager® product—why is it not supported on Windows 7, Windows 2008, etc.? (Also Vista though that doesn't come up more than twice a year).

The answer you usually get from our support staff is that the licensing doesn't work on Windows past XP. It's true; there is an important API call used in the older version that is no longer supported.

We don't usually go into this much detail on the phone, but the main reason is that when Microsoft released Vista, they also mandated that the developers follow their new security model. The part that affects our customers is that Windows services can no longer use shared resources (like network folders and printers). Services can only use locally attached disks and printers. In order to use a shared resource, the service has to use login credentials.

The way we've done this in the new version of RPM, starting with version 5.0 and continuing with the current 5.1 series, is to let you add user, password and domain to a device. If you do, then we use this login temporarily, only while we're using that device for your print job. As soon as the print job is done then we "log out" automatically. This approach is what Microsoft expects. It works well and even supports multiple threads.

Other bottlenecks included:

  • printing only one job at a time
  • using the Windows registry for settings and job information (it's great for casual storage but not as a database)
  • inability to print while you were running a filter program
  • and many more beyond that.

As far as why we couldn't do that with RPM 4.5, I should point out that version has its roots in Windows NT. It's essentially the same product we were selling in the late 1990's with a few updates. It performed well in the older environments, but the effort to "patch" it to work with the new systems of the past few years (not to mention the next years) was just not worth it. RPM 5.0 and beyond is a near total rewrite from RPM 4.5.