>I found, that one of the form was using different class from different classlibrary.
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>My grid class has HightlightBackColor set to 182,202,234 and it looks like a default setting. That grid class uses 49,106,197 and it also looks like a default. I think, it depends on if the grid is in Read Only mode or not. I also just found, that the developer set that property for the particular form. I guess, I have to set this color to dark blue in my grid class so the colors match, though I do not like to change visual appearance. Or I need to discuss it with the manager first...
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It shouldn't matter if the grid is read only or not, unless you're looking at the DynamicBackColor instead of the HighlightBackColor. But since, as you point out, one of the forms is using a different class from a different library, that class probably has a different default setting. You'd have to open the class itself to confirm that.