Symptoms
When executing the tool enum.exe from ApSdk, the user receives the following error message:
"Debug Assertion Failed!
Program: E:\Program Files\Citrix\CSSDK\APSDK\vctest\export\export.exe
File: afxtls.cpp
Line:229
For more information on how your program can cause an assertion failure, see the Visual C++ documentation on asserts."

Cause
When you go through the code, you see that the error occurs when creating a farm object on the following lines of code:
try
{
pFarm = new FarmObject;
}
catch(...)
{
}
Therefore, not only enum.exe but almost any other application from the ApSdk , that has to create a farm object, experiences the same problem.
Resolution
This problem was fixed on post-Service Pack 2 hotfix XE102W013.
Check that the version of the apsdk.dll on the user's environment is newer than the version of the same file contained on that hotfix.