SAP Note 15447 - Error in navigation / inconsistent object list

Symptom:
Workbench:
1. An object is not found when you navigate by double-clicking the
mouse, or the system asks whether you want to create the object,
although it already exists.
2. Double-clicking on a program object causes message "Main program
for include ... not found" (MSG EU127) to be issued
3. The object list of a program (or function group) is inconsistent.
That is, entries are missing or some entries are doubled.
4. Displaying the program object list or double-clicking on a
program object causes an endless loop.
() EUNOTE, EUNAVIGATION, EUWORKBENCH Additional key words
Cause and prerequisites

Error in the program index (of the main program)

Solution
You can reconstruct the program index (for the main program) at any time.
Option 1: Transaction SE80 (Workbench) -> Program -> Generate
(or object list Program -> Update). This option is
available in Release 2.1A and later.
For error case 4 (endless loop), a problem exists if
a user has set the critical program as an entry point
in the Workbench.
In this case, the initial screen of the Workbench will
never appear, and you cannot generate the index as a
result. The colleague who set the program as a entry point
should be able to help you in this case.

Option 2: Load the main program into the program editor and update
the index.
This option is available in Release 2.1I/2.2C and later.

If, once you have carried out the above actions, the error situation still occurs, this means that the syntax error in the program is so serious that the system is not capable of analyzing it. This usually involves a literal error in which the single quote (') at the end of the literal is missing. Once you correct the syntax error, you can reconstruct the program index.