SharePoint Error:The workflow could not update the item

          SharePoint 一个workflow在用户测试的时候一直报这个错误，但是我自己的账号就没有问题，最后发现其实是权限不够。授予Contributes权限后就好了。

   Error：The workflow could not update the item, possibly because one or more columns for the item require a different type of information.