A couple of months ago I installed Skyrim, modded it, and played it for around 300 hours. During this period I could ALT-TAB back and forth between Skyrim and Windows 8 without any problems. Now I have just reinstalled Skyrim the same way (as far as I know), on the same computer, but when I try to ALT-TAB back into Skyrim I get http://s13.postimg.org/kxschj4xj/skyrim_alt_tab.png. It looks like that for around 20 seconds, then crashes to the desktop.

Do you have any advice on what might cause this behaviour?

PS: I've never played in windowed mode - not now, and not earlier.

TES games have always been pretty unstable if alt-tabbing in and out of game -- they are not really designed to be left running in the background while some other app takes over.

Ok, thanks. It's odd though, because I never had a single problem with my frequent alt-tabbing during the first 300+ hours I played Skyrim.

I always press ESC to enter the menu before alt-tabbing, and I'm using very modest texture-enhancing mods this time. I'm using a high-end computer too, with GTX770 and SSD. I use around 80 mods, mostly from the STEP Guide.

Game never crashes to desktop like that i do alt-tab out frequently are you running some ENB's or any custom d3d9.dll plugin i have read somewhere sometimes that crashes the game like that

I'm using SkyRealism ENB, which I also used without problems during the 300+ hours before I reinstalled. The only difference now is that I'm using the recent version of ENBSeries (v.0.217, formerly v0.168).

I tried alt-tabbing in vanilla Skyrim, without ENB or mods, and the problem still occurs. Odd. Perhaps it'll be resolved in a future GeForce driver. I'll just avoid alt-tabbing for now. Thanks for the feedback.

Yes, it's normal. When you get this screen, don't wait, click on it's bar (the blue thing with Skyrim written in it on your image) so that the window pointer disappears and then alt+tab again into the game.