This has been an ongoing issue for several years. We have an Android tablet app using a WebView browser (based on Chromium) and supply links to PDF files stored in Box. Sometimes, the response is "preview not available" and the option to download is presented (which is not an option for us). The same thing happens occasionally in regular computer-based browsers such as Chrome, but this is rare.
I have occasionally been able to fix this by re-uploading the same PDF file to Box - sometimes this works and the preview is successful. I am guessing there is a background process that builds the preview; if so, it does not always seem to get triggered.
As another data point, I see the same thing on iPhone using Chrome or Safari as the browser, so I do not think this is specific to our Android use case. Even stranger, I have examples where the preview works OK on Android but fails on the iPhone.
Any insight into this would be appreciated.
Thanks!