When you export a JPEG with a watermark, the thumbnail embedded in the JPEG doesn't contain the watermark. This causes the Windows 8.1 File Explorer to show thumbnails of the exported pics without a watermark, confusing users who are checking to ensure their pics were properly marked. (It appears that the OS X 10.10 Finder doesn't use the embedded thumbnails, so watermarks show up in Finder thumbnails.)To reproduce, export a JPEG with a watermark, using these export options: Image Format: JPEG, Quality: 60, Include: All Metadata, Watermark with PNG watermark. Open Windows 8.1 File Explorer on the containing folder and do View > Extra Large Icons to view the folder's files as thumbnails. Note that the thumbnail of the exported pic doesn't show a watermark. Use Exiftool to extract the embedded thumbnail:
exiftool -b -thumbnailimage myfile.jpg > thumbnail.jpgThe extracted "thumbnail.jpg" is missing the watermark. Setting Limit File Size To: 100,000K (100 MB) avoids embedding a thumbnail and thus avoids this problem. (Julie Kmoch pointed out that setting a limit uses a different code path in LR.)See this thread for a user's report: https://forums.adobe.com/thread/1882527 Some but not all of the problems reported in this thread are possibly caused by this bug: http://feedback.photoshop.com/photosh... on LR CC 2015.1 / Windows 8.1.