I don't quite know a solution to this, truth be said, but I don't believe it's any kind of missin' file. Rather, a glitch most users end up facin' every now 'n again. I've had it many a times before myself but normally just re-typin' up the biography works as a solution for a while until the glitch rolls 'round again.
If I may make a suggestion, ye' could always type up a biography for yer character(s) here on the forums. Ye' then won't be character limited, won't have to worry about it glitchin' out, will be able to apply certain fonts and other decorations, and even provide visuals of what yer character may look like (this is especially handy for those with characters branchin' off the character models). Then ye' can make a custom tinyurl to pass around to others who are interested in gettin' to know yer character and they can read till their hearts content.