Is it acceptable to only use the 'else' portion of an 'if-else' statement?

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Sometimes, I feel like it is easier to check if all of the conditions are true, but then only handle the "other" situation.

I guess I sometimes feel that it is easier to know that something is valid, and assume all other cases are not valid.

For example, let's say that we only really care about when there is something wrong:

object value = GetValueFromSomeAPIOrOtherMethod();

if((value != null) && (!string.IsNullOrEmpty(value.Prop)) && (possibleValues.Contains(value.prop)))
{
    // All the conditions passed, but we don't actually do anything
}
else
{
    // Do my stuff here, like error handling
}

Or should I just change that to be:

object value = GetValueFromSomeAPIOrOtherMethod();

if((value == null) || (string.IsNullOrEmpty(value.Prop)) || (!possibleValues.Contains(value.prop)))
{
    // Do my stuff here, like error handling
}

Or (which I find ugly):

object value = GetValueFromSomeAPIOrOtherMethod();

if(!((value != null) && (!string.IsNullOrEmpty(value.Prop)) && (possibleValues.Contains(value.prop))))
{
    // Do my stuff here, like error handling
}
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