I'm using Lightroom 5.7 and just bought a new iMac (OS 10.10.3). The transfer from my old iMac didn't go as smoothly as I would have liked but I've finally got my Lightroom catalog restored. But I'm not able to export from Lightroom. The message I get is Unable to export. An internal error has occurred: Assertion failed: err == noErr
Does anyone know what I can do to get things back to normal.?
Same thing happened to me. It turned out that I had "subfolder" checked under the "export to"; however, there was nothing input in the subfolder box. Perhaps the LR code got confused with a null value . Anyway, when I realized this & unchecked everything worked fine