Abobe-indesign, issues caused by missing assets
One quite common mistake made by first time users of the indesign software package is to assume that assets such as pictures which have been inserted into the document are in fact saved in the document. This is not the case as by default indesign only keeps a thumbnail of a given asset within the indesign file itself and then references the location of the original file whenever it is opened. This helps to keep the indesign document from becoming overly large, and when exported, the exported file will contain all of the assets at the correct resolution. However, if you are working on an indesign file, you need to be aware that if you open a file in a location where it cannot reach some or all of its assets, it will break. This can manifest in many ways including but not limited to, the file complaining it is incompatible and refusing to open properly, the file refusing to print and the file showing large blank spaces or highly pixelated versions of missing assets. To avoid this, a good practice is to make a dedicated folder for each indesign project, and store all the related files in that folder with the indesign document. That way you can copy the folder containing all the assets when you need to work on it elsewhere.
To fix this problem any broken assets must be removed and readded. If the file refuses to open, open it on the machine used to create it with the same external storage devices plugged in using the same drive letters.