GB ▁max . ▁( S and isk ▁has ▁tested ▁that ▁the ▁biggest ▁memory ▁card ▁size ▁possible ▁on ▁the ▁C 9 0 5 ▁is ▁ 1 6 GB .) ▁ ▁Design ▁Four ▁colours : ▁' Co pper ▁Gold ', ▁' I ce ▁Silver ', ▁' N ight ▁Black ' ▁and ▁' T ender ▁Rose ' ▁ ▁Start up ▁fail ures , ▁data ▁cor ruption ▁and ▁hardware ▁issues ▁For ▁some ▁users , ▁the ▁C 9 0 5 ▁can ▁suddenly ▁fail ▁to ▁startup , ▁and ▁instead ▁just ▁show ▁a ▁black ▁screen ▁with ▁the ▁back light ▁turning ▁on ▁and ▁off ▁repeatedly ▁. ▁ ▁This ▁problem ▁happens ▁due ▁to ▁internal ▁data ▁cor ruption ▁( ca used ▁by ▁the ▁phone ), ▁and ▁can ▁only ▁be ▁fixed ▁by ▁rest oring ▁the ▁phone ▁to ▁its ▁original ▁software / f irm ware ▁— ▁meaning ▁that ▁all ▁personal ▁data ▁will ▁be ▁er ased . ▁On ▁some ▁occasions , ▁this ▁problem ▁can ▁be ▁fixed ▁by ▁using ▁the ▁Update ▁Service ▁software ▁that ▁comes ▁on ▁the ▁CD ▁( or ▁from ▁Sony ▁Eric sson ' s ▁website ). ▁However , ▁personal ▁data ▁will ▁still ▁be ▁er ased . ▁ ▁Users ▁are ▁recommended ▁to ▁regularly ▁backup ▁their ▁data ▁using ▁both ▁a ▁Memory ▁St ick ▁— ▁for ▁photos ▁and ▁contacts ▁— ▁and ▁using ▁the ▁software ▁My Phone Ex plorer ▁to ▁back ▁up ▁other ▁data ▁to ▁a ▁PC . ▁A ▁startup ▁failure ▁can ▁be ▁predicted ▁when ▁the ▁text ▁message ▁menu ▁can ▁no ▁longer ▁be ▁opened . ▁ ▁A ▁hardware ▁fault ▁that ▁has ▁been ▁reported ▁frequently ▁is ▁that ▁the ▁ear pie