I've had this issue (both with RoboHelp 6 and 8) when inserting an image that wasn't saved in the RoboHelp project's directory.
The solution I found was that once you insert the image (from the non-project's directory) into your topic, delete the image from your topic and then insert it again, but this time, make sure to select it from the RoboHelp project's directory.
I'm assuming that you could also first save the image to the RoboHelp project's directory and then insert it from there - but, I didn't try this.
We occasionally have this problem. Try opening the image in Photoshop and then saving as a different type like .jpg. It seems to me that our problems were mostly with bitmaps. Sometimes resizing by even one pixel can also help. ... Give it a try.
Something to consider if you are using the venerable and industrial strength PhotoChop is that you often need to "flatten" an image and save.
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I am using PS elements 2. it does everything I need and I know how to use it very well. I flatten everything before making my .jpg. We have not had this problem for a long time because we make .jpg files. We also use a standard set of image width so our pages will display and print with the same look and feel. 200px 300px 550px 600px with a couple 50x50 icon images.
I am fighting RH8 right now. The upgrade took out half my project. I am really pissed. Trying to downgrade for 2 hours now. I think Robo has hosed my computer. I may have to break down and pay for help. I'll give it another 2 hours.
I think I've fixed it.
These are images I've used before, and they are in the correct project directory. The issue (apparently) had to do with the length of the pathname. At least, that's what I'm guessing. When I moved the whole project directory up a level, everything worked fine. Exact same directory down a level, nothing works at all.
I saw the same thing with long file names. Filename too long, and the image won't import. Cut it down a few characters, and it comes in fine.
So, I guess there's a limit on the length of the path name, although these folders were only one level below the default and the images were at the top level of the project.
Anyway, all working fine now. Thanks for the help.
I think you get 132 characters in the total file length. 128 plus the period and the extension. Many things won't work if you go over this length. I have made it practice to name my topics and folders with what ever length name but edit the file name and pare it down as much as possible to avoid the problem in the length of the path.