Sometimes, when trying to Continue or Load the game from the main menu, the game will begin loading, but stay loading "forever" (slides will still change, and the roulette wheel will still spin, but the game will never actually load - tested up to 25 minutes). This is easily solved, just clear the cache on your Hard-Drive (Xbox 360) and it should then allow you to load.
This issue also affects the PC version of the game in Steam. It is unrelated to the size of the save file, and it does not seem to be caused by a "corrupt save." In the absence of a permanent solution, you can load from within the game.
Instead of selecting Continue or Load from the title screen, select New Game. Skip the cut scenes, and as soon as you are able open the game menu and load your saved game. NinjaPeanut
You can also try to remove some of your earlier savegames in the file itself. That worked for me.
One way I found to fix this problem was to make sure that my resolution in the display settings of the original menu screen is the correct resolution. After lots of testing around trying many things (unsuccessfully) to fix this problem I realized that the resolution had changed itself to lower than what it should be. After changing it back to normal the problem was fixed. (Anon)
Try increasing your iPreloadSizeLimit in your FalloutNV.ini file to 52428800, which is double the original value. The file is located in your Documents\mygames\FalloutNv folder.
This seems to be a working fix for anyone having trouble loading.
For what it's worth (who frickin knows when it comes to this bug infested piece of crap), the 'forever' loading screens and the lag after fast travel/going from one game world to another seems to be directly related to the size of your currently saved game. For example, you can have all DLCs installed and have accomplished almost everything in the game and your save file could be around 12 to 14 Mbs. However when you start a new game, your saved game will be extremely lower than this, like around 900 Kbs. This is probably why in a new game you can play for awhile without any issues (except known bugs, like Nash not leave the Casino in Primm after you re-establish law there). Because of all the issues with this game, it might be wise to complete only 2 of the DLCs per playthrough to help keep the file size down. Again for what it's worth, hope this is helpful. --Kid Ego 22:17, October 3, 2011 (UTC)
Or your mods has some features bloating the save games. Better read carefully about each mods you want to use. i know at least one mod wih a feature like that, though the modder do comment carefully in-game whenever i use that aspect. second reason is that it's possible to have a hostile on your fast travel entry spot, so you can not ft there. It's not as pronounced on mojave (possible because of all the time testing and fixing) but I encountered it 1st time in Zion, then Big mt. Strangely, divide doesnt seem to have that bug.Laclongquan (talk) 07:56, April 23, 2013 (UTC)
some people suggest to 'check file integrity' if you have a steam install. be aware that it does not work and if you have mod instaled they will be broken and you will have to reinstall everything.
also, there is a similar bug introduced to TTW it is said that a hotfix was introduced there is hope to see a more permanent update-fix to resolve this issue. Dartagnant croc tranchant (talk) 21:55, May 14, 2015 (UTC)