Applets acting strange

My applets are sometimes on my task bar and sometimes not zorin os 5 ultimate 32 bit on a Toshiba Satellite A135-S4527 when the applets aren't there i shutdown the computer and restart it and usually they are right back where they should be i also now have an error that just showed up that says "The panel encountered a problem while loading "IndicatorAppletCompleteFactory::IndicatorAppletComplete" do you want to delete the applet from your configuration?" should i delete it and why are my applets mysteriously disapearing and reapearing any help would be appreciated.

thank you swarf will do and let you know how it worked out

I deleted the factory applets and added appets to the task bar I even added the dictionary applet i noticed that the internet connection applet is far right on the task bar. when i used the dictionary applet the window for this applet showed up half way on the screen and halfway off the screen i believe the applets may actually be on the task bar but they are to far right and off the screen. not sure what to do about this maybe i will just try using the mac os look of zorin although i am more familiar with windows seven. Any help with this would be greatly appreciated.