From what I have read from Adwords advisor in webmasterworld and from other experts in various forums pausing a adwords pay per click campaign will not give any negative effect to the results nor will it affect Quality score of a website.

Its very normal to pause a run a campaign for various reasons. Reasons like hosting problem and website goes down, insufficient funds , invalid clickss can always arise and these are valid reasons to stop / pause a campaign. Google is well aware of this I am sure there are no bad effects on Quality Score in adwords campaign,

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