Help with whitish blur in photios

[magda5E88]

Hi. Sorry if this is a stupid question but I'm a beginner with fixing poorly shot photos and I'm tryin to teach myself how to do it.  I'm usually good at googling how to fix issues but I actually don't know how to describe this one and everything I've tried has ultimately led me to how to correct photos taken on a cloudy day or how to fix pver exposed phtotos. And I tjink this is more than just being over exposed, no?
Can anyone tell me what causes this and how I can fix it?

Thank you so much.

[c.pfaffenbichler]

I think an overall Auto Curves Layer and an additional one with a Layer Mask to address the left side might help. 

Edit: And whether such a »brute« first Adjustment may be useful one can judge by looking at the Histogram. 

Notice how much space is left empty on the left side. 

[magda5E88]

Wow! That looks great. I'll give it a go. Thanks so much.

[Norman Sanders]

Can anyone tell me what causes this and how I can fix it?

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The effect you asked about is referred to as "flare" or "lens flare."  It is caused by non-image light entering the lens at such an angle that it bounces around within the lens elements, affecting the image. In your case, it is the angle of some of the light comng from the window.

In the old days lens flare was quite common but later improvement in lens coatings have reduced its image-damaging effect. One of the things you may do to reduce lens flare is to use a lens shade that blocks the non-image light from reaching the lens at an extreme angle..  

When I was a young man (a long time ago) working with a clunky view camera outdoors, I always wore a wide-brimmed hat. I would take it off an hold it over the top of the camea so that it could cast its shadow over the lens and eliminate possible lens flare. Today a handy lens shade affixed to the front of the lens does the job equally well. 

[magda5E88]

Thanks so much for the explanation.

And for the workaround. Although, I don't take the photos. I'm just the one trying to learn to fix them after the fact. But I do appreciate understanding what's happened and why.