There are two main errors that may occur when scanning. The first is that the document you’re scanning has breached the file-size limit configured into the Xerox. Because Xerox scan-files are carried by the Outlook email system, the Xeroxes are pre-configured with a size limit which will prevent over-large files from being transferred to the network, and potentially slowing the email service down. A handful of Xeroxes have had the file-size limit extended to the maximum possible (usually one in any building), but for obvious reasons most machines will still limit file-size. PDF is the most size-efficient format; if you alter the scan settings to produce TIFF files (for example) these will be much larger and more likely to fail for large scans. Note: It’s impossible to issue guidelines on what files might fit comfortably under the limit – it depends on the scan resolution settings on the MFD you’re using, and also the density of text/images on your original document.
The second reason for failure is a loss of communication with the network. If the Xerox fails to scan at the ‘Transferring to network’ stage (the touchscreen should indicate the various stages in the scan process), then the error sheet should indicate an ‘SMTP failure’. A restart of the Xerox MFD may rectify if this; if not, log a call for investigation by the Print team.