[Tango Mike]

Sorry for not being specific enough:

The first validation failure occurred when "delivering" the ePub to iTunes using the iTunes Producer, the application on my computer that allows me to produce the "package" that is uploaded to iTunes. They don't say what the validator is, so I tried the ePubcheck on my computer to see if there was a difference. As far as I can tell, the long list of errors is identical, so I'm guessing that iTunes uses ePubcheck as well.

To test whether the doc>htm>Calibre>ePub flow might be part or all od the problem, I just finished an experiment by using InDesign to export the indd version of my novel to ePub, then used ePubcheck to validate it. I got no errors, only warnings about fonts that weren't embedded. (I expected that, because the indd version of the novel was created for the print version rather than the ePub. It has more fonts and styles than the doc version, but I wanted to see what would happen.)

With that experiment done, I then tried to deliver to iTunes the ePub file created from the indd file. I expected a different result because this file had (as I understand it) "passed" the ePubcheck on my computer because there were no errors in the result.

But no, this file failed the iTunes validation with what appears to be the same previous long list of errors. I've pasted in examples from two sections of errors below and one complete section that doesn't repeat the same error multiple times. (I read in a thread that we are supposed to replace certain text with "dummy" text when sharing it here, so I did that where I thought that refers to.

"parameter ErrorMessage = ERROR ITMS-9000:Invalid URI in manifest dummy_split_000.htm : Illegal character in path at index 5: dummy_split_000.htm" at Book (MZItmspBookPackage)" Note: There are a bunch of these with increasing three digit numbers following the "split_" text and prior to the ".htm" text. The numbers increase to "038".

"ERROR ITMS-9000: "Invalid URI in NCX file dummy_split_005.htm : Illegal character in path at index 5: dummy_split_005.htm" at Book (MZItmspBookPackage)" Note: These also repeat with the same increasing numbers up to "038" within the error message.

Then the following block:

ERROR ITMS-9000: "image file cover.jpeg is too short" at Book (MZItmspBookPackage)
ERROR ITMS-9000: "dummy_split_000.htm(1309): attribute "link" not allowed here; expected attribute "class", "dir", "id", "style", "title" or "xml:lang". This error occurs 39 times." at Book (MZItmspBookPackage)
ERROR ITMS-9000: "dummy_split_000.htm(1309): attribute "vlink" not allowed here; expected attribute "class", "dir", "id", "style", "title" or "xml:lang". This error occurs 39 times." at Book (MZItmspBookPackage)
ERROR ITMS-9000: "dummy_split_001.htm(1310): element "span" not allowed here; expected element "address", "blockquote", "del", "div", "dl", "h1", "h2", "h3", "h4", "h5", "h6", "hr", "ins", "noscript", "ns:svg", "ol", "p", "pre", "script", "table" or "ul" (with xmlns:ns="http://www.w3.org/2000/svg"). This error occurs 3 times." at Book (MZItmspBookPackage)
ERROR ITMS-9000: "dummy_split_001.htm(1310): attribute "clear" not allowed here; expected attribute "class", "id", "style" or "title". This error occurs 4 times." at Book (MZItmspBookPackage)
ERROR ITMS-9000: "dummy_split_004.htm(1310): element "b" not allowed here; expected element "address", "blockquote", "del", "div", "dl", "h1", "h2", "h3", "h4", "h5", "h6", "hr", "ins", "noscript", "ns:svg", "ol", "p", "pre", "script", "table" or "ul" (with xmlns:ns="http://www.w3.org/2000/svg")" at Book (MZItmspBookPackage)
ERROR ITMS-9000: "dummy_split_004.htm(1312): attribute "name" not allowed here; expected attribute "accesskey", "charset", "class", "coords", "dir", "href", "hreflang", "id", "rel", "rev", "shape", "style", "tabindex", "target", "title", "type" or "xml:lang". This error occurs 35 times." at Book (MZItmspBookPackage

So, when I see all this with a file that works beautifully on the iPad, I'm more than a little confused, to put it mildly.