There is no means to update from SP3.0 to SP3.1, because ' x% {9 b p. @! y5 I% J8 Z# e- V$ e$ ` W
"Please note that the only difference between SolidWorks 2008 SP3.0 and SP3.1 is production support for Microsoft Windows Vista 64-bit, so it is not necessary for customers on other operating systems to download this Service Pack. "