There are a couple things going on here. First, when you change your group in /etc/password it changes which group you belong to, but that won't have any effect on files that are already created. From now on, all files you create will have group try, but anything from before won't change.

That is why in your second post you needed to do the chgrp. When you did the chgrp try /user/abc, that will change the group for JUST /user/abc. If you want it to change the group for everything below you need to tell the chgrp command that. In Solaris it would be:

chgrp -R try /user/abc

If you are using a different Unix version just check the manpage for chgrp to verify that the switch is -R for you as well.

Hope that clears it up for you.