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After spending the last week mucking about with an install of Windows 7 x64 SP1 that I really need to do a repair install on (vs doing a clean install), I'm stumped as to how to get around this problem of the "not enough disk space" that occurs at the 74% mark during the transfer of files and settings.

What I've figured out

  1. For some reason the 100 MB System Reserved Partition is missing
  2. I can create the System Reserved Partition using the Windows 7 manage feature.
    But regardless of whether I make it 100 MB or 256 MB I get the same error.
  3. The actual hard drive itself is 1.5 TB with 1.2 TB free space.
    So there is plenty of room on C: for what the repair install has to do
  4. Using EASEUS Partition Manager isn't recommended, so the 100MB partition has to end up after C: instead of before. Not sure if this is the issue.

I followed the instructions I found elsewhere

  • making the partition NTFS
  • no drive letter assignment
  • NTFS format, full format (not quick)
  • named as System Reserved

The issue might has to do with the attributes being given to the System Reserved Partition. I'm not able to mark the partition with the right attributes.

The info I've found suggests that the System Reserved partition should have system, active and primary as it's attributes. But the one I create only gets marked as as primary. I tried marking it as active. But that took the active status off C: drive (and when the repair install failed the rollback failed too as a result).

I could use a partition manager program via the UBCD to mark the System Reserved Partition appropriately. What do you think? Is there something else I'm missing?

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Do you have a memory card or USB pendrive plugged in during the installation. I asked because there have been issues where windows outsmarted itself by unpacking stuff in 'the most empty location'. And a fully empty 256MB pen drive (100% free space) is preferred over a 99% free partition (even if those 99% are on a huge multi-TB drive) – Hennes Dec 31 '12 at 2:54
No, no USB drive or any other similar dev plugged in. I did a startup repair this afternoon just on a whim, and it seemd to need it for some reason (this was after I created the System Reserved partition again). I noted that the W7 install DVD when doing the startup repair treated C: drive as D:, and D: drive as E: - not sure that I've noticed that before on other systems, so not sure if that's significant or not. Perhaps it might explain why it's popping out the error message? And if yes, how do I fix that? – Peter Dec 31 '12 at 3:46
Since you do a repair installation you re-use the existing partition of your HDD, right? You didn't create new partitions. Thats most likely the reason why you won't have a normal 100 MB System Reserved Partition. Please check this site and scroll down to Method 1: Use Existing Partition or Partitioning Scheme – nixda Dec 31 '12 at 6:52
The system I'm working on has a dual-boot to Windows 8. I'm pretty sure that the system originally had the 100MB partition (since I originally did a standard clean install in Jan of this year), so possibly the dual boot, however that was done, has tweaked the system? It's not my computer even though I did the original install for a friend, so I don't know how he sorted the dual boot. Even so, I would have thought that the repair install would still work regardless. Any other thoughts? – Peter Dec 31 '12 at 7:36
If you have that many errors in the OS drives filesystem: reformat. (aka, do a full reinstall after you have made a good backup). As for the 100MB partition: win7 runs fine without it, as long as you do not use bitlocker for full disk encryption. (The OS needs some place to start from before it can start decoding an encrypted FS). – Hennes Dec 31 '12 at 14:23

The problem can be solved by applying the following steps:

  1. Delete the partition where you want to install, and the 100MB partition.
  2. Now the disk has unallocated space. Select the drive and install Windows.

The problem is caused by insufficient space in 100MB reserved partition 0.

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