Re: New subtypes that i have created in the Type and Attribute Manager are not visible in the Folder contents

It sounds like the OOTB table view could be corrupted. You could try deleting the all view and letting Windchill recreate it (backup of database tables recommended first):

SQL>create table tableviewdescriptor_bkup as select * from tableviewdescriptor;

SQL>create table activeviewlink_bkup as select * from activeviewlink;

SQL> delete from activeviewlink where ida3a5 in (select ida2a2 from tableviewdescriptor where name='com.ptc.windchill.enterprise.folder.folderResource.ALL_VIEW');

SQL>delete from tableviewdescriptor where name='com.ptc.windchill.enterprise.folder.folderResource.ALL_VIEW';

SQL>commit;

Restart Windchill