OK, now I'm really out of options...
Just tried connecting the Ultimaker to Cura on Windows XP - on an old Macbook Pro with bootcamp installed.
Installed Cura first, tried to connect - no luck, serial port could not be found.
Then I installed Arduino IDE, tried to get the board detected there, again it didn't work.
The device manager only shows an unknown device connected to USB.
So far I have tried the following OS's (the first three all on the same HP Elitebook 8530w laptop):
Windows7 64bit - error code #43, device not recognized
Ubuntu 12.04 on virtual box - no serial port found
Ubuntu 14.04 on dual-boot / separate partition - no serial port found
Windows XP SP3 (Macbook Pro from 2007) - device not recognized, no serial port found
I did all the tests with both the original arduino board which came with the UM1 kit, and a new (original) arduino which I bought at a local electronic store.
Only thing left would be to test with the third (!) arduino board I've got now, a replacement which was sent by Ultimaker this week. However I doubt that I got two malfunctioning boards here, would be very odd indeed.
Any suggestions how to proceed with this one? Never thought it would be this difficult to get the printer going...
Many thanks in advance for your advice!
Cheers,
Fran