Kernel Mustard

The first day of the Vista compatibility lab was… long. We got to the campus at about 9:00, and didn’t leave until 11:00 PM. This is the second time I’ve done something like this at Microsoft (the first was at Driver DevCon 2003, getting our network drivers running on NDIS6). It’s always a productive time – plenty of food, water, experts, books, and computers around so that there really are no impediments to getting real work done.

Vista is going to be an interesting challenge. The UAC stuff changed a lot in the last six months, and our software doesn’t quite interact perfectly with it yet. On the upside, the things that I thought were working – the drivers, for example – are indeed working. Other things are mostly clean-up work for code that was probably in need of clean-up anyway. There haven’t been many (any?) Vista-only changes that would break on downlevel OSes, which reinforces my claim that, if you are careful and code to the API in the documented way, you’re way less likely to break compatibility in the future.

Some of the experiences haven’t been quite so great, though; Ken found a seemingly very severe problem with IpHlpApi route addition, for example, and we’re seeing slightly different behavior from some other APIs in IpHlpApi as well – I fought with IpReleaseAddress for a while when it started returning a new (undocumented, of course) return code

And, of course, there are the major breaking changes – for example, GINA DLLs are gone, which may not mean much to 99% of software vendors out there, but if you happen to need a GINA replacement, you have to re-write that code completely and produce a credential provider instead.

In the annoyances category, there are things like icons looking bad (the dark grey task bar is hell on colorful icons) and high-res support in various places. And, ideally, we want to fully embrace the UAC system rather than fighting with it, which raises some interesting product design questions.

We made way more progress than I thought we’d make on day 1, and we still have most of the week ahead of us, so I’m optimistic that we can actually finish what we came here for. So far, so good, at any rate.