Hello. I’m new here, so sorry if I posted this in the wrong place. I have experienced a very bad glitch with Halo: Reach. Basically sometimes, when I save a map, it saves it under another map’s name. So for instance, if I created a map and called it “Canyon”, then I update it and next time I play on it, it is the older version and the newer one replaces another one of my maps. It usually isn’t terrible when it is in temporary history, but some times I may not have played on that map recently, so there’s no way (that I know) to recover it. Thanks for any help.
This is a known issue since the Bungie days, and unfortunately maps cannot be recovered and no fix has ever been found. The only known way around this is to save the map you are making using the “save as new map” option and renaming it every time (using your example, renaming it from Canyon to Canyon 2 and increasing the number with every update). Then just delete the older versions whenever you update you maps.
Hope this helps.