I would think you need to set something in Irfanview.
Open Irfanview
Go to "options" heading
Select "Properties/Settings"
Click "Full Screen/Slideshow"
Click "Fit to Screen large images only "recommended"
HP epc40, XP Pro SP3, Irfanview 4.35 (latest version) - this is saved to an external harddrive, with no trouble since installing on 11/12/11, until last week.
About 2 weeks ago, when I would double click on an image, the image would open into something so large, one cannot tell what is on the screen.
I have done View>display option 1:1, but it does not do anything for the images.
I have tried reducing (-) the magnification and resaving the image, with no change.
Does any one have an answer? I am sharing raw photos due to having inoperative photo editing software.
Irfanview does not have a Help section. I cannot find out how to start a thread. The creator does not want any contact for this type of topic.
I look forward to solving this soon. Thanks.

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