Currently have parallels desktop version 4 and wondering if a conversion of the guest os is required like it was going from version 3 to version 4. After the upgrade the convert process did not work for me, and I had to reinstall everything from scratch. So before i upgrade to version 5 wondering if this same convert process is required, because the potential of this type of a disaster is not worth the upgrade.
bglasner PD4 and PD5 virtual machines are compatible, no convertion required as it was with 3rd version, except Parallels Tool upgrade.