There are quite a few web pages that discuss this particular error message that might appear when you start up a computer that has a UPS from APC connected to it and where the computer is supposed to be able to monitor the UPS and to provide warnings when the power situation changes and even automatically shot down the computer where necessary. The error message basically means that the service monitoring the UPS is not working. The pages that show up when you search for this error all discuss various software issues that might be preventing the service from working properly and suggest a variety of software solutions mostly involving which version of the software to upgrade to to rectify the problem.
Reinstalling or upgrading the software might fix the problem but there are a couple of other possibilities that none of the pages dealing with this error even mention. The purpose of this page is to discuss those options that all the other pages appear to ignore.
With the constant warnings about security holes in Java many people will have sensibly decided to remove it from computers that don't need it and to at least disable it in web browsers when it is needed on the desktop. Now the PBE service itself probably doesn't need Java but the web based version of the monitoring software does use Java and so if you have uninstalled Java then actually being able to open the monitoring software in your browser to see if anything there offers any help in working out the solution - particularly after you have reinstalled the software and the error message still appears - will not be available. You do need Java installed on the computer but you can still have it disabled by default in the web browser. When you try to access the monitor via the web page you will get a popup asking if you want to allow Java to run for the page and can allow it just for this specific page without compromising the security of your computer.
One thing to check for from the monitoring software is to check if it can actually recognise what type of UPS it is that you have it connecting to for the purpose of the monitoring. If the monitor can see and report on the UPS then you have narrowed the problem down to being specifically related to the PBE service. If the monitoring software can't see the UPS then the problem isn't with the PBE service it is being caused by the computer being unable to communicate with the UPS.
A communication problem between the computer and the UPS could possibly be a hardware problem and checking the actual hardware setup is the easiest place to start in this situation. The problem might very well be as simple as a cable having come loose.
The other possibility is a timing issue where the service is simply unable to start because of conflicts with other processes starting up when the computer first boots. In this situation the service can be started manually after the computer finishes booting up.