What do you see when you don't see a topic?
Seriously, do you see a blank screen? Do you see your topic title? If the topic is supposed to appear in a new window or a popup window, does an empty window display?
We had a problem a bit like this where an empty WebHelp page displayed after conversion from RH6 to RH8. It was caused by a style in our .css that had a negative left indent. When we changed the negative indent to 0, it displayed again.
I believe we received a "page cannot be displayed" message when we clicked
on these topics...
This can be any number of things. Can you be a bit more specific. How are the topics referenced? If in the TOC are they internal or external to the RH project? If external, check you link. Are they a page to an external file? if so, check the link and ensure the file is in your baggage. This is just for started as it is hard to give further advice without some further info. Please help us so we can help you.
Read the RoboColum(n).
In addition to what has been offered so far, if your output is WebHelp, you might ensure that you try enabling the "Use lowercase file names". This can help if your web server is UNIX based. The option will convert all topics (and references) to lower case. This can "fix" links that appeared to be broken before. For example, maybe a topic was named:
But you linked by typing it and made it all lower case as in:
This would be a broken link on a UNIX server.
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