You can upload a maximum of 5 files, each up to 48MB. Supported files include image, .doc, .dot, .wbk, .docx, .docm, .dotx, .dotm, .docb, .xls, .xlt, .xlm, .xlsx, .xlsm, .xltx, .xltm, .ppt, .pot, .pps, .pptx, .pptm, .potx, .potm, .ppam, .ppsx, .ppsm, .sldx, .sldm, .pdf.