Linux - Workstation 10.0.2 - VM slowess in Kubuntu 14.04

Hello.

I used a VM with Kubuntu 13.10 (64 bit) and Windows 7 (64 bits) as guest.

I reinstall my laptop with Kubuntu 14.04 (64 bits, from scratch) and also WMware workstation 10.0.2 (it used to already be 10.0.2 before the reinstallation).

I imported the existed VM (File > Open). I also verified that the WMware tools are corretly installed.

However since that, the VM is really slow to boot (It stuck in a black screen around 30 seconds, around 5 minutes in windows starting screen and when it started, the performance in the VM are really bad). I checked the VM memory, CPU but everything seems like before. Before in used to boot in 45 seconds.

Do you have any idea of the problem?

Thanks