Error downloading iOS 18 update on iPhone

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If your iPhone or iPad won't update - Apple Support (IN)

stemac88 wrote:

Hi all. Every time I try to update my iPhone I get an error message (after it has apparently Dow loaded) to say ‘error downloading’.

I have 15gb of space (asks for 7.99gb) and tried the usual tricks but it always ended up with same error message.

thanks

[Re-Titled by Moderator]

Original Title: Can’t download iOS 18

What usual trick?