Missing Breadcrumbs Caused by Similar File Names

Question

Using RH9
Producing both WebHelp and HTML Help (with missing breadcrumbs the same in both)
Using only the SSL option to generate the breadcrumbs
As in some previously posted cases, a few topics in a large project are missing breadcrumbs. There are no quotation marks or other unsual characters in the file names or titles. I was able to narrow down one error to something I could fix in a test project.
In the following HHC entries, the breadcrumbs were missing from the "General Ledger Processing Recap (AM72)" topic when the help was generated. (Everything after the second item is a bookmarked TOC entry, with no breadcrumbs expected, but I left those items in the example in case they make a difference.)
<item name="General Ledger Options" link="SYSOVER\General_Ledger_Options.htm">
<item name="General Ledger Processing Recap (AM72)" link="SYSOVER\General_Ledger_Processing_Recap_AM72.htm">
  <item name="What is a General Ledger Processing Recap?" link="SYSOVER\General_Ledger_Processing_Recap_AM72.htm#What_is_a_General_Ledger1">
  </item>
  <item name="Benefits of Using the General Ledger Processing Recap (AM72)" link="SYSOVER\General_Ledger_Processing_Recap_AM72.htm#Benefits_of_Using_the">
   <item name="User-Defined Recap Report" link="SYSOVER\General_Ledger_Processing_Recap_AM72.htm#User_Defined_Recap_Report1">
   </item>
   <item name="Ease of Defining Interface Data" link="SYSOVER\General_Ledger_Processing_Recap_AM72.htm#Ease_of_Defining">
   </item>
   <item name="Operations Balancing" link="SYSOVER\General_Ledger_Processing_Recap_AM72.htm#Operations_Balancing1">
   </item>
  </item>
  <item name="Components of the General Ledger Processing Recap (AM72)" link="SYSOVER\General_Ledger_Processing_Recap_AM72.htm#Components_of_the">
   <item name="Section" link="SYSOVER\General_Ledger_Processing_Recap_AM72.htm#Section">
   </item>
   <item name="Line" link="SYSOVER\General_Ledger_Processing_Recap_AM72.htm#Line">
   </item>
   <item name="Item" link="SYSOVER\General_Ledger_Processing_Recap_AM72.htm#Item">
   </item>
  </item>
  <item name="Defining the General Ledger Processing Recap (AM72)" link="SYSOVER\General_Ledger_Processing_Recap_AM72.htm#Defining_the_General">
   <item name="Completing Worksheets" link="SYSOVER\General_Ledger_Processing_Recap_AM72.htm#Completing_Worksheets">
   </item>
  </item>
  <item name="Defining the Recap" link="SYSOVER\General_Ledger_Processing_Recap_AM72.htm#Defining_the_Recap">
   <item name="Entering the Recap Definition Online" link="SYSOVER\General_Ledger_Processing_Recap_AM72.htm#Entering_the_Recap">
   </item>
  </item>
  <item name="Defining the Section" link="SYSOVER\General_Ledger_Processing_Recap_AM72.htm#Defining_the_Section">
  </item>
  <item name="Defining the Lines" link="SYSOVER\General_Ledger_Processing_Recap_AM72.htm#Defining_the_Lines">
   <item name="Valid Escrow Source Codes" link="SYSOVER\General_Ledger_Processing_Recap_AM72.htm#Valid_Escrow_Source_Codes">
   </item>
   <item name="Entering the Recap Line Definition Online" link="SYSOVER\General_Ledger_Processing_Recap_AM72.htm#Entering_the_Recap_Line">
   </item>
  </item>
  <item name="Verifying the Recap Definition" link="SYSOVER\General_Ledger_Processing_Recap_AM72.htm#Verifying_the_Recap">
  </item>
  <item name="Building the Recap Definition Files" link="SYSOVER\General_Ledger_Processing_Recap_AM72.htm#Building_the_Recap">
   <item name="Processing Recap Structure Validation Report" link="SYSOVER\General_Ledger_Processing_Recap_AM72.htm#Processing_Recap">
   </item>
   <item name="Printing the Report Structure Validation Report and the Sample General Ledger Processing Recap" link="SYSOVER\General_Ledger_Processing_Recap_AM72.htm#Printing_the_Report">
   </item>
  </item>
</item>
</item>
But when I changed the file name of the parent topic from General_Ledger_Options.htm to GenLdgrOpt.htm, the breadcrumbs appeared correctly in the output for the parent and child topics.
This stragegy for fixing the breadcrumb problem seems to be hit-or-miss. For example, I've tried the same approach to fix another topic and have had no success so far. Is there anything about how breadcrumbs are generated that would explain how renaming the file would fix the problem?

Answer 1

Rick,
I think you are right about the file name length being an important factor, but the cause doesn't seem to be as simple as a too-deep nesting level. I was able to fix the problem in another topic by shortening the file name of the topic that preceded it at the same level.
The one hard case that remains is a topic that contains a lot of bookmarked subheadings. I found that if I cut that topic's number of subheading TOC entries to 33, the breadcrumbs for the topic worked, but with 34 TOC entries, they did not. My best guess is that there is a limitation of some kind on the internal aggregation of TOC information -- including information about siblings and children.
By the way, I also tried inserting breadcrumb placeholders, instead of automatically generating them. That caused RoboHelp to crash (instead of just failing to add breadcrumbs to the offending topic). When I removed the placeholder from the bad topic, it worked OK with the other topics.