Parallels has released Parallels Desktop 4.0 Build 3540, a maintenance update to address problems with caused by upgrading Parallels Desktop 3.x to Parallels Desktop 4. Build 3540 corrects a number of bugs, including a case where Windows stops while booting during the upgrade, and where a Boot Camp partition can't be accessed after the upgrade, or an error message appears stating that it "failed to configure the Boot Camp partition." The code at this link is only the English build; Parallels said it would release builds localized to other languages in the near future.

If this update has solved any problems upgrading from Parallels Desk 3

Before the Build was released, readers have reported problems with upgrading to 4.0. These readers wrote before the new build was released.

Christopher Thomas:

My upgrade failed when attempting to convert my 3.0 image to 4.0 compatible image. It appears that the problem was that a) Windows was asking to get reauthorized, and b) there were Windows updates pending. By uninstalling and reinstalling Parallels, and then restarting Windows each time it failed, it eventually worked through the issues and became usable.

Another reader:

My drive is 53 percent full. I used Parallels Desktop 3, Windows XP Pro SP2 it was ok. Parallels Desktop 4, unless I've configured it wrong is way slower and is a system hog from the default upgrade with no tampering. I don't really know where to tamper to get the full impoved promise, but I sure don't see it. I run a MacBook Pro Core 2 Duo with Leopard 10.5.5.

Harry Erwin:

Bunch of installation problems.

1. Parallels Setup is quietly installed on the bootcamp disc, to run the next time the system is booted into Windows XP. This came as an unexpected and unwanted surprise.
2. Parallels Setup then fails when it can't find PSCRIPT.NTF.
3. The virtual machine can't see the keyboard or mouse on my MacBook Pro when I start it up, so it is completely useless.

Eric Scheuermann:

Upgraded from version 3 without success. Stuck in an infinite loop of "Please wait while the virtual machine is being upgraded...". (on every restart) While open, the program seems to be upgraded and the virtual drive is working.

The install is totally different from previous upgrades. (Personally, I prefer the look of version 3.0 compared to 4.0.) I reinstalling v3.0. I'll wait for the fixes to be applied before trying again.

I was looking forward to using the new version, which enables Directx 9, for specific programs that I use for work. (Microstation XM, ArcvMap 9, etc)

If you've seen these types of problems, if the Build 3540 update fixed them.

See also our Parallels Desktop Tips and Reports page.

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Parallels update fixes reader's problems