When I'm trying to "view collection variables" in the debugger nothing happens. I'd expect either an error message or the view to appear.
(PLSD 7.1.1.1339)

To obtain some more diagnostic information, can you modify the shortcut and add the debugsql parameter? For example:

"C:\Program Files\PLSQL Developer\plsqldev.exe" debugsql

Reproduce the problem and send me the debug.txt file that is generated in the PL/SQL Developer directory.

I got the same result when trying to "view collection variables" on a package that didn't have debug info. Adding debug info resolved it.

I have sent the debug.txt.
Worker's solution is not working for me either.
An additional hint: "view collection variable" is enabled almost everywhere in the test window ( not only for collections).

As debug.txt does not help here ... can I do something else to isolate the problem?
I have already tried:
recompiled again to ensure debuginfo is really there
used dual session instead of multi session
granted dba to the debugging user
XP/Home + XP/Professional platform for PLSD
Changed plsd to automatic home selection
even installed 1341
As far as I remember (but I 'm not sure) simple collections used to work with 7.0.3.

I have the same problem. We user version 7.1.0.1337
In a package we have an associated array variable of type:
TYPE my_visit_array_type IS TABLE OF NUMBER
INDEX BY VARCHAR2 (10);
When trying to debug the variable using right click "View Collection Variable" nothing happens. When I do "Add Variable to Watches" it gets added and as value just shows (Collection). When I click on the "..." field there a Text Editor window opens and in it again just the text: (Collection).
I also remember that it worked watching collection variables in debug in the previous version. Hope that helps to sort out the problem.
Best Regards,
Berny

Well for me it works, as long as the variable is not a parameter or has been assigend the value of a parameter. When that is the case, and i want to inspect the collection, plsql develpoer completly hangs though

Looks like that works with a oracle 10 db though, it only hangs on a 9.2

My database version is 10.2.0.2 and it doesn't hang for me either, it simple does'nt work (but til is right: it is possible to create a test case with a "local only" collection where it is working)
But it would be nice to make it work like the "inspect" function of Oracle's SQL-developer...

Possibly it depends not only on the db version, but also on the sqlnet version. I've seen collection related problems depending on sqlNet.