hello friends i am working a site on six month, my site serp is stable on yahoo and google but it is not stable on bing some time my all the pages is removed by bing. i need your help
We can't do anything nor offer advise without knowing your site's url, niche, etc. Provide these details and we'll try to help.
It's hard to say. Did you use any blackhat mehods? Maybe Bing detected it while the others SE's didn't.