Import of CSV address list 'hang' in Outlook 2003 in Vista Busine

Dear Expert,
I've a Toshiba Satellite M200, Dual Core, 512MB RAM, installed with MS Office 2003 sBE. When I import a CSV format of addresse, Outlook 'hang'. I repaied my PST using scanpst, repair MS Office and even uninstalled MS Office and install it again. The problem still persists! Could it be that the RAM is too low and would the upgrade of another 1GB help to resolve it? This laptop can hold up to 2GB of RAM.