Serial Number (System): Not Available
Last week I noticed my USB ports were not working. Before taking my Macbook for repair, I first tried upgrading OS to Lion OSX (previous was Snow Leopard), which did not solve my problem. Then, I took it to repair. Today I brought it back and I noticed Serial Number was not available though "About this Mac" menu. Did anyone face this before?
PS: After upgrade I did not check this menu
MacBook, Mac OS X (10.7.2)