Black Lines through text - on return command?

[DrGs A]

I have a 2019 Apple Macbook pro - with Sonoma OS 

and Adobe InDesign 2024 

I've been working on a book - with 6 chapters  

it is only in the 6th chapter that I've begun to get these black lines appearing through my text - 

they seem to be generated when I press the 'return' key?

Can anybody help?

What Have I done wrong and

How can I get back to normal ? - Gary 

[James Gifford—NitroPress]

Also, this is kind of lost in the passing (mentioned but not emphasized): if it's not a cryptic setting, as suggested, and the file is corrupted, the first thing to try is an export to IDML, then open that file and save as INDD under a new name. That "purge" often fixes frustrating little document faults like this one, which could have been caused by any bump in the editing or import path. (Both Derek and Robert mentioned this, but only briefly, and I don't see where it was tried.)

[DrGs A]

Thanks James - I am a bit green here so forgive my ignorance - but I'm just putting it into IDML format right now - and then back to INDD  - So Ill let you know how it goes - Gary 

[DrGs A]

Hi James & Robert - I have just copied the file into IDML and re saved as INDD (under a new title) as suggested but it has made no difference - 

I think I'm just going to rebuild that chapter - but I'll have to get to it after I have finished the rest of the book. Thanks for your advice and just being there - apppreciated  - Gary

[Robert at ID-Tasker]

@DrGs A 

Can you share your file - in part on in full - you can click on my nickname if you prefer to send it on priv.

[DrGs A]

Hi Robert (& Derek ? )- attached below should be a copy of Ch#6.indd with the 'Black Line' issue - I'd be grateful if you can locate the problem. As I'd mentioned it is not coming up in the other Chapters - Gary

[James Gifford—NitroPress]

There's no attachment. 😞

[DrGs A]

Apologiies and Thanks James  I've reloaded  -

At 23.7 MB it is under the limit - perhaps I didn't wait for the file to load properly ?

Currently loaded @ 23,156 KB - G

[DrGs A]

Hmmm - I can't see that its loaded (as yet?)  - OK one more time with feeling? G  

[Robert at ID-Tasker]

Hmmm - I can't see that its loaded (as yet?)  - OK one more time with feeling? G  

By @DrGs A

Still nothing. 

ZIP it and upload to some sharing service - then post link. 

[Derek Cross]

InDesign records all your events, over a period these build up and can cause a document corruption. Saving as an IDML file clears out this crud and you start with a new clean document. If you are working on an InDesign document for some time, this process should be part of your normal workflow. That's why I suggested doing this (and resetting the InDesign preferences) at the beginning of this thread. Even if they don't sort out your particular issue they are worth doing just to eliminate the possibility.