Since you have installed many CS products, in order to determine extensions of which product is being loaded when EM stops, you can remove one product once a time then launch EM again. You don't need uninstall that product, you only need open XManConfig.xml from install directory or configuration subdirectory of that product, find following line: <Data key="SupportedInSuite">CS5</Data>, and change CS5 to other value temporarily, for example, CS4, then save this file. Launch EM again, if it works properly, then Loading extensions of this product causes this problem. We can check it further.
You can also create a empty file named ExManLog.YES in same directory as Adobe Extension Manager CS5.exe, and see log files in C:\Users\<UserName>\AppData\Roaming\Adobe\Extension Manager CS5 to assist troubleshooting.
i got it , thx . next time I will try it.
Yes, I uninstalled Paython and its working fine again. No "Loading Extension" hang.
saved my time