Beginning in 2009, the compact flash card was no longer a standard accessory for the DPO4000 and MSO4000 series. DPO4000 and MSO4000 can use: -Firmware versions lower than version 2.06 any standard Type 1 compact flash card up to 2 GB -Firmware version higher than version 2.06 any standard Type 1 compact flash card up to 4 GB Update your firmware by using Tektronix Software Download Finder: http://www.tek.com/downloads/ To purchase a compact flash card from Tektronix use part number 156-9413-00 (Type 1 Compact Flash 32MB).