I found this via a google search for "Can't allocate the DIB handle", and I can't help but speak my mind on the topic...
My story is quite similar to those who have already complained, but before you give me the stock "The program's not meant for gif files that big" speech, hear me out.
I have my own webcomic, and the strips are 800x800 pixels. Not every strip is animated, but I always use the Easy GIF Animator for the ones that are. I started off with the trial version, but I upgraded to the full version fairly quickly. After upgrading, I never had these memory problems. Most of my animations were small, of course, 5-10 frames, but I had a fair number that ended up being 30, 40, even up to 75 frames, depending what was going on. I did have one ambitious 475 frame animation... but no computer I or my friends own was powerful enough to handle that one... it got chopped down to 170 frames, and was just fine. Yes, you read that right, 800x800 pixels, 170 frames, all .png files, and the animator was able to handle it perfectly. You can see it here if you like. I should also mention, I've made 24 comics this way, 12 at 800x200, and 12 at 800x800, and the biggest file among them is 385kb. Most are in the range of 20-50kb.
Just recently, however, the gifan.exe file mysteriously disappeared from the folder. I went to use it one day, and it wasn't there. I dunno if it was a virus or what, but I had to revert back to the free trial. Naturally, I didn't save my information from when I first upgraded...
The comic I'm trying to make now is 50 frames, but every time, when I get to the 37th frame being loaded, it gives me the Can't allocate the DIB handle error, at which point my 2 gigs of memory are maxed out. I attempted loading them 10 at a time, and was able to get all 50 frames in, but when I tried to adjust the frame speed, it went back to the DIB handle error. I have to find fault with the fact that the program used to be able to handle animations exactly like this just fine, and now eats more memory than a cartload of Vistas. Not to mention the fact that no single program should be using up 2 gigs of RAM all on its own, regardless of what it's doing, or the fact that "gifs aren't supposed to be that big". There's absolutely no reason for it.