I need CM 5.0.3 because it contains some specific devices like PoE catalysts.
I had 5.0.2 and I've installed CM 5.0.5 (I thought it already contains 5.0.3 and 5.0.4 but it does not). Now if I try to install 5.0.3 I get:
ERROR: Cannot install Suite of applications for network management(Campus Manager).
ERROR: You are trying to install an earlier Campus Manager version (5.0.3)
ERROR: over a later version (5.0.5).
How to delete CM 5.0.5 ?
Well, RME and Campus are two different applications, each with their own device support. If you need RME support for these switches, you need to make sure you have Cat2960 RME device package version 4.3.
If you need to update your RME packages, go to Common Services > Software Center > Device Update, and check the boxes next to Common Services and RME, then download and install all available updates.
If you are still seeing problems with these switches in Campus, then post the details of those problems.