This is really starting to drive me nuts. I am warming up my accounts, letting them age for a bit before I use them. However, I still get this error about 50% of the time. Sometimes, I can delete the campaign, start a new campaign exactly the same, and it won't do it. Sometimes I get impressions during it, sometimes I don't. Sometimes it is triggered even by adding new keywords to a campaign. Your ad isn't showing for this keyword right now due to a system delay or some other reason. Contact support if this issue does not resolve itself soon. I run a lot of accounts so it isn't practical to have a discussion with support every time this becomes an issue because it's, well, always an issue. Any idea what triggers it and how to avoid it?