My Nikon D7000 raw files all have a magenta cast to them when imported into Adobe Lightroom 3.5, and I wasn't shooting on multiple exposure. I am running Windows 7 64-bit, and have Adobe Photoshop CS4 as well as a trial version of Adobe Lightroom 3.5 (testing to see if I would like to buy as I can't read my raw files in CS4).
If I convert my raw files to DNG, and then view them using camera raw (CS4), the magenta cast is gone. However, if I view those same DNG files with Lighroom, they have the magenta cast. I have tried re-importing my catalogue, but everytime they all have the same strong magenta cast. Help would be much appreciated as I can't seem to find anyone else having this problem, and I otherwise can't access my raw files.
The most likely reason is the monitor profile. Either recalibrate the monitor or if you haven't got the necessary hardware/software try switching to the sRGB profile in lieu of the default monitor profile
It isn't calibration of the monitors. It's a problem with camera raw compatibility with Lightroom. I had this problem with LR3 until they released a newer camera raw update. Now with LR4 and shooting Nikon D800 I'm seeing the same magenta cast again, with calibrated monitors. It's specific to LR (don't see it in other image editing programs with raw files), so you know it isn't a monitor issue.
I managed to fix it actually. I don't know if you can update camera raw with just LR, as I did my update through PS5. So looking for updates in PS5, it updated my camera raw and now the problem is gone. Last time, with LR3, it was a stupid thing Adobe did, where you could only get the most current edition of camera raw by upgrading to PS5 (and I had been on PS4) ... so after upgrading to PS5, I could finally get the correct camera raw version. Hope it helps.