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It appears the the TrueCrypt (TC) boot loader is large so is split between the MBR (446 bytes) and a 32KB hole after the MBR but before the 1st partition. And TrueCrypt seems to be hardcoded in finding that 32KB hole just after sector 0 (i.e. pure MBR scheme). So when we have a GPT (which occupies the first 34 sectors/17407 bytes) instead of an MBR, this 32KB hole should be slider further away - which it does NOT.

I think the solution is "straightforward" where instead of just looking for 32KB free space (For the remaining TC boot loader) just after the MBR, it should be flexible to look for 32 KB after the GPT too. In short

// made up variable names
if (MBR)
{
    startOffsetTCBootloader = sizeOfMBR;
} 
else if (GPT)
{
    startOffsetTCBootloader = sizeOfGPT;
}
// plug back startOffsetTCBootloader into other calcs/jumps

Although I have a background in assembly AND boot loaders, none of it was in x86 assembly. So it'll take me time in fixing this myself. Plus I'm SUPER busy with a few other projects, so sadly don't have the luxury to pick a pet project (right now). So this is a call for help to my fellow developers who may be in a better position :)

So: does anyone know how to modify that? It's best if this went back to the core repository but forking isn't such a bag idea since the main branch seems unresponsive.

FYI, I did write to the TC developers but I think my email went into a black hole ... so gotta fix it ourselves. GPT disks are the future, so this fix should have a long live and many other use cases too.

Useful links:

  1. Truecrypt (TC) source: http://www.truecrypt.org/downloads2
  2. Truecrypt (TC) license: http://www.truecrypt.org/legal/license
  3. My user level issue: https://superuser.com/questions/361515/install-truecrypt-on-a-macbook-for-whole-disk-encryption-of-the-win7-partition-i
  4. More technical details (someone else): http://www.wilderssecurity.com/showpost.php?p=1590313&postcount=3 by someone else.
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DeepSpace101
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    Wait, you are using Stack Overflow to file a feature request? – Skyler Saleh Nov 27 '11 at 02:54
  • I'm asking for help/code snippets to help me work around that limitation, ASSUMING the change is localized. The official feature request has been posted on TC's official forums too - this is a call for an independent work-around or perhaps even a fork. – DeepSpace101 Nov 27 '11 at 19:59
  • Unless you are personally going to design the work around or fork, stack overflow is not the right place to put this. People here are fine with helping you and hinting you in the right direction, however we will not do your entire project. – Skyler Saleh Nov 27 '11 at 21:55

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