3 TB/GPT ext HDD not recognized in TI Home 2011 w/ Plus Pack

I have a 3TB GPT external hard drive, partitioned in half, with NTFS. I have Acronis TI Home 2011 with Plus Pack. The program won't pick up those two partitions. I switch to Disk Mode and select what looks like the 1st part of my drive, it says it's 2.7 TB in gray letters, but when I select it, it says the backup size will be 9.6 TB! I uncheck that and select the 2nd part of that drive & it says the backup size will be 172 GB. Nothing makes sense. Both partitions are nearly full with over 1 TB each used.