Dell Latitude XT Tablet PC owners have been noticing that Vista SP 1 has been strangely absent from Windows Update. I talked to Dell Tech Support about this, as did Steve Seto, and this is what we’ve learned from our Dell tech support rep ( who has been working like a laser beam in tracking down this issue for us):
Ok so I talked this one over with a few guys in the lab and I think I’ve found out why you’ve been unable to install SP1 on your XT. Essentially, they were able to get it on the one in the lab and found that once SP1 was installed, the system then failed to boot back into Vista. So it appears that for the moment there is something incompatible between SP1 and the XT. We have not received word on what exactly is the culprit. I will keep my ears open for any alerts and updates we receive and inform you of them as soon as possible.
As soon as we get an update from the on the SP 1 issue, we’ll update everyone. Until then, we advise all XT owners to avoid SP 1, even if you have it available through MSDN.