We recently ran into a situation with a customer who was uploading very large validation files to a Dolphin 7600.  The customer was having sporadic problems where the uploaded file would not be completely uploaded.  We discovered that the size of the truncated file was always the same as the amount of free space on the device before the upload.  It turns out that when overwriting the file, the device did not reclaim the free space immediately, so the new file had to fit in the remaining space.  We solved the problem by using the DeleteFile function before uploading the new files, which did allow the device to reclaim the free space.

We've added a Knowledge Base Article about this topic, and we will address it in a future release by automatically deleting files before receiving them.