not enough space

im trying to transfer a 4GB file to an external HD that has 132 GB free. but it tells me theres not enough space. this doesnt happen with smaller files. How do i get this file onto my external HD? My local disk has 7.17 GB free.

One of three things has happened here.

#1 -- The file is larger than (2^32)-1 bytes in length. That "-1" part is an important bit that gets missed frequently in these discussions, just like saying that "4 bits have 16 possible states which range from 0-15". It's the same thing, because file lengths range from 0 to 4,294,967,295.

#2 -- The FAT32 partition you are copying to has may have become invisibly crammed with lost clusters/chains. This is pretty rare for disk of this size, but still wise to check it out anyway every once in a while.

#3 -- The boot sector is incorrectly reporting the amount of free spacce on the partition. I have an external FireWire/USB hard drive connected to my machine (250GB divided over 4 FAT32 partitions of various sizes) and I have to run some disk-tools every other day because of this problem. No actual data loss is occuring, it's just that the drive's controller-chipset and the OS (Win98) don't seem to jive for some reason about counting clusters.



In any case, if you are using FAT32 for any reason, make sure that it is no larger than 120GB, but I like to limit it to 100GB just for the sake of round numbers. If you have a FAT32 partition bigger than the 128GB limit, then you run the risk of major data loss in pre-Win2K operating systems... frankly, I wouldn't take the chance in any OS.

The main problem is that the addresses will wrap around, and the read/write function will go back to the beginning, blindly assuming that it is working near the back-end of that partition. It's kinda like if you took a 6hr VHS cassette and recorded a 15hr program on it. Normally the tape would simply stop when full (then rewind and auto-eject), but imagine a scenario where the tape on the spool could continue being recorded on past the end and back onto the beginning as if they were spliced at there--it would wrap around two and a half times before the program was over!!

The advise I give is simple:

Split you FAT32 partitions so that they are NEVER LARGER THAN 120GB.
Use disk checking tools regularly to make sure the partition is in good working order.
Be mindful of the file size limits of FAT32.