I correct any system errors if needed.
I correct any system errors as needed.

1. Which preposition above is grammatical? and natural?
2. If both are possible, what is the difference in meaning?

Please advise. Thank you.
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Comments  (Page 2) 

The proper usage is either as needed or if necessary.

I feel more comfortable asking for help at the writer's corner and will utilize this again if needed.

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