I run a set of large, inter-linked spreadsheets that are used for a Financial Model. We were pushing the memory limits of 32-bit Excel, so we switched to 64-bit (2010). I have recently been running into an issue where random files seem to get corrupted during the save process. The files appear to save correctly, but the next time I try open them, one of them hangs and never opens. There appears to be no rhyme or reason as to which file experiences the issue...it varies. Furthermore, the error does not occur every time. Sometimes all files save properly. It seems that around 50% of the time, one of the files gets corrupted. I have found that 32-bit Excel will still open the corrupted file (even though 64-bit will not), and simply saving the new file once it has been opened in 32-bit corrects the issue. I am then able to go back to 64-bit and open the file and it works properly. Any info as to why the files are randomly getting corrupted would be appreciated. Thank you.