This is most likely a RAM issue but it may be that your RAM slots on your motherboard have become defective. If the latter, you will need to replace the motherboard, which may mean buying a new computer if a motherboard cannot be found at a reasonable price (try ebay as well Panasonic and other computer dealers)
However you should start by finding out what RAM is in your computer which means opening it if it won't start.
see the reference manual which can be downloaded at http://www.panasonic.com/business/toughbook/computer-support-download-manuals.asp
Go to p119 - there you will find a slightly more informative description of what the problem is likely to be (RAM module). I don't know where the RAM modules are situated in your particular model of CF29, you will need to find out. Remove all of them. (see ref manual on how to do this - it looks like the standard method for laptops). Replace one of them in the approved fashion: ensure that it fits well: usually it is easy to tell when this has happened - see other guides for upgrading laptop RAM modules or videos (you tube has many) for this stage if you do not understand the Panasonic ref manual - I found the IBM T40series guide at www.lenovo,com very easy to understand. Now try starting the computer. If it gives the same error, remove and the RAM module and try again. If this doesn't work try the other RAM slot if your computer has one with the same memory module. If that doesn't work repeat the process with the other RAM module [if the computer had one]. In this fashion you should be able to determine whether and which RAM module is defective or if it is one of the slots on the motherboard. If there is only one module and slot, you will need to try reinserting the RAM and if that doesn't work using another known good stick of RAM of the correct type (not all RAM sticks of seemingly the correct spec, will work though: best use a reputable brand). This will tell you whether it's likely to be the original RAM or the motherboard, or just that the RAM had become improperly seated.
While carrying these operations the computer should be powered down and have the battery removed. Observe anti static precautions and do not force anything.