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I was making a volume with trucrypt and I set the size to be 12MB. I tried copying 10 files totalling 7.13MB (on Disk) but got an error saying I did not have enough space. Why is this? Is it because I'm copying from an NTFS format to FAT?

Celeritas
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    How about looking how big your usable space is? Other than that, 12MB is tiny. Each FS reserves space for metadata, independent of Truecrypt etc. – deviantfan Jul 13 '15 at 06:07
  • @deviantfan not sure I'm following. There's GBs worth of space on the physical hard drive. – Celeritas Jul 13 '15 at 06:52
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    If you´re using only 12MB for your volume (for your data + metadata together), why does the rest of the hard drive matter? – deviantfan Jul 13 '15 at 09:45
  • @deviantfan I thought that was your question, I have no clue what you're saying/asking. – Celeritas Jul 13 '15 at 18:42
  • I think you don´t understand what a volume is. If you have a Truecrypt volume of size X (or any partition of size X), it´s limited to size X and not a single byte more. In this limited area, not only your files, but some amount of file system support data has to fit in. Modern FS aren´t designed to be used on such tiny areas, eg. BTRFS wants *at least* 1GB for itself, even if you have not a single own file. FAT32 is not so greedy, but 12MB is still a problem. ... If you want to have a truecrypt are in your HDD which should hold 12MB files now, but could have more, make a much bigger volume. – deviantfan Jul 13 '15 at 20:54

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"Setting the size to 12 MB" doesn't tell much.

Some file systems do not scale well downwards. FAT32 will reserve space for directory structures and file allocation tables, which will give you an overhead of unuseable space. The actual space left for storing files will be the volume size minus that overhead.

After creating the volume, open it (it will be empty) and check what the available size actually is.

Even so, differences in allocation block size may mean that you cannot store what on disk A are 8 megabytes onto disk B even if you have 8 megabytes free there (the "File size (on disk)" is what matters here). After each file copy, verify how much the available space has shrunk.

LSerni
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