I installed this for a friend after spending many unsuccessful hours trying to install the Sony Ericsson software supplied with the K800i.
I was astounded by how quickly MyPhoneExplorer installed. It worked immediately and I was very impressed.
How comes an individual can write such good software when a big conglomerate like Sony Ericsson can only produce highly bloated software that often doesn't even work (as witnessed by all the postings one finds on the Net when trying to get information on the installation).