Windows 7 - not enough disk space?

I'm trying to upgrade Vista to 7 on an Acer laptop. The hard drive has a single 75Gb partition, with 50GB free. But Win 7 upgrade tells me there isn't enough drive space to carry out the upgrade.

I've defragmented, done disk cleanup etc, but to no avail. What could be happening? Help much appreciated...

Instead of doing an upgrade, I would format the drive and do a clean install...less problems in the end...

Well, Tews is right but if you are keen on upgrading then do the following to recover some more space on your hard drive.

1) Turn off hibernation. Run CMD as admin, at the command prompt type: powercfg -h off

2) Turn off system restore.

Also, see this thread

Not enough space for upgrade installation

Also, does your computer have an OEM recovery partition? As a last resort, you can delete that partition and use that space but make sure you make and test recovery dvds before doing that.

If you have the Acer Upgrade kit, you can boot the Windows 7 install media DVD to clean install as Tews wisely suggests.

The installer is driver-complete, with newer arriving soon via optional Windows Updates. Any missing drivers or apps can then be found on the CD included in the kit, or on the Acer Support Downloads webpage for your model.

Bills information is correct and will give you more space. I, however, do not think it wise to turn off SR unless you have a system image on an external HD. Trust me without SR it is just a matter of time until you experience a problem that will make you sorry that SR is not available. I know, I have seen and answered 100's of posts.

Sadly, I didn't buy the acer upgrade; I bought a standard home premium upgrade. After a lot of wrestling I've discovered why it won't install - when I boot from the installation disk and try a custom install I get the messaged "windows can't install to this partition; it has been reserved by the computer's manufacturer".

Checking with Gparted shows drive C as a single partition; there don't seem to be any recovery or hidden partitions. Is there any way I can turn off this acer reservation and use the upgrade rather than formatting and starting from scratch?

Yes, that is likely the Acer EISA hidden partition. Here is how to get rid of it as I did on several machines:

Delete and Remove to Unlock EISA Hidden Recovery or Diagnostic Partition in Vista My Digital Life

Use Diskpart or free Partition Wizard bootable CD to manage your HD as Gparted is not that good with Windows 7.

Thanks so much to all who helped. Annoying Acer hidden partition now gone, disk nicely formatted, windows 7 installing merrily as I type.
Fingers crossed...and thanks again.

Good thread Guys, one and all.

All who have helped are glad that your problem has been resolved.