true crypt hidden volume, insufficient space

[thenewbieencryptor]

Hi, i have problem with creating hidden partition in true crypt
Not enough free space for the hidden volume! Volume creation cannot continue.
I have chosen option to create hidden file, created password to outter volume tc, it generated the volume and mounted it. I copied data that can be revealed. Then clicked next and it was supposed to check how much space is still available to create hidden volume. Then this error appeared. I have chosen outter volume to be 550 gb and data copied to it were about 100 gb with about two thousand files (i have not chosen option to allow files bigger than 4 gb).
What could be the reason? There is space available because volume is about 550 gb and files copies about 100 gb.
I know tc is not supported anymore but it was still not hacked (i mean source code is available and no serious security holes were found).

[lucid]

What is the file format of the partition you set it up on? NTFS? FAT32? Also, and I shouldn't have to ask this but, how big is the partition you are setting this up on? Because if you made the outer volume 550gb, then there better be a lot more the 550gb available if you want a hidden partition as well.

[thenewbieencryptor]

Hi, format is the default one for outter volumes that do not require > 4gb file, i.e. fat32. Well, by partition i am setting this up on I guess you mean partition that is visible directly from operating system, right? Unfortunately this is not much bigger than 550 gb, i have lelf some space available but it is less that size of my outter volume. I did not see anywhere in the wizard or tutorial information that i need to leave more space available on system partition (outside outter volume) than outter volume itself.

I could not find information about the steps that true crypt takes to create this outter and then hidden volume. Does it mean it needs at least as much space on system partition as big the outter volume is? If yes, it looks like the only way to create my hidden volume is to create it again, but smaller, so that i have at least, let's say 350 gb empty after outter volume creation if my system partition is 700 gb? The error message in true crypt was not quite descriptive about the exact reason.

PS By system partition I mean what is visible from operating system, even without tc (e.g. 700 gb). By outter partition i mean size of the file on system partition, which can be mounted by password that can be given if requested (e.g. 650 gb with 100 gb with data - it means appending something above100 gb would overwrite hidden partition). By hidden partition i mean what is available by mouting that big file with more secure password (of size 650 gb - 100 gb = 550 gb).

[thenewbieencryptor]

Also, and I shouldn't have to ask this but, how big is the partition you are setting this up on? Because if you made the outer volume 550gb, then there better be a lot more the 550gb available if you want a hidden partition as well.

Why do I need more space on system partition?

I have performed check with very small hidden partitions. Let's say I had 700 gb system partition and 200 gb available. I have created tc file that was set to 1 gb. After it created outter volume, my system partition had 199 gb available. Then I have copied data to outter volume (25 mb), tc claimed i can create hidden volume of about 75 mb, i have chosen 50 mb and it created hidden volume. My system partition was still 199 gb (exactly the same size as just after creation of outter volume).

So why does true crypt require empty space on system partition to create hidden volume if it is created within disc space for outter volume?

[lucid]

Well that was a little hard to understand but I'll do my best. So, if your harddrive is 500gb, and you create a 550gb outer volume, you should obviously be able to see the problem with that. Idk what operating system you are using but whatever operating system it is, you are obviously going to need some extra space for what is already on your hard drive. If you are trying to encrypt the entire drive then you are doing it wrong and need to look into TC's full disk encryption option. I'm thinking that's what you should be doing since you are creating a rather large drive. What do you need 550gb of encrypted space for?

Also, unless you have a 1.5tb hard drive you are probably getting close to running out of space on your harddrive with the size of the outer volume alone, and the hidden volume should be around the same size as the outer volume. There's no point in creating a 550gb outer and a 1gb hidden volume.

EDIT: It doesn't create it inside of the Outer Volume. You are obviously adjusting some setting incorrectly. Your misunderstanding comes from the fact that it doesn't display exactly how much space is available. For example, it wasn't telling you that you have EXACTLY 203776mb(199gb), it was telling you that you have ROUGHLY 199 gb. That could mean 199.3 gb. So by using up 50 more mb that was too small of an amount to make it change from 199gb to 198gb.