The file extensions blocked by default by SharePoint are: ade, adp, app, bas, bat, chm, class, cmd, com, cpl, crt, dll, exe, fxp, hlp, hta, ins, isp, jse, lnk, mda, mdb, mde, mdt, mdw, mdz, msc, msi, msp, mst, ops, pcd, pif, prf, prg, reg, scf, scr, sct, shb, shs, url, vb, vbe, vbs, wsc, wsf, wsh
