Error: Invalid Data. Review all error messages below to correct your data.
The preflight report reports an error (or warning) on low res images.
Cause The error (or warning) in the report is generated by a check in the PDF Profile. Within the PDF Profile you can define to have images below or above a certain resolution reported as an error (or warning). You can also define in the PDF Profile to have images resampled to a certain resolution.
Solution 1. Do not define a resample value in the PDF Profile. 2. InDesign by default has in its PRINT settings within category Graphics "Optimized Downsampling" active. This setting will cause all high res images to be automatically resampled to 150 dpi when printing. Set this Graphics parameter to NONE to avoid automatic resampling by InDesign.