I know this topic is covered elsewhere in this forum, so I would not ask if I was not desperate and had tried everything I could already.
I have a large PhD thesis with over a hundred images in it written in lyx. When I try to export to pdf, for three particular images I keep getting the error "cannot determine the size of graphics"
To try to remove this error I have tried the following:
Specifying the scale graphics % in the lyx graphics dialogue box.
Manually specifying the exact width and height of the graphics, in cm, in the lyx graphics dialogue box.
Deleting the original .bmp files and re-exporting the images as .bmp files from the graph creation software I am using (Sigmaplot in case anyone knows it.)
Converting .bmp files to .jpg files, and when that did not work, converting to .png files, which did not work either.
These three files look to me to be very similar to other files which I have exported from the same graph creation software, but I am not receiving any errors for those. So at this stage I am completely out of ideas.
Any help would be greatly appreciated. Also I am not a programmer and don't understand coding very well, so assume you are responding to a complete dummy when it comes to latex etc.