Dealing with slow data files issues with Quickbooks?
Slow Network Performance of Large Data Files in QuickBooks 2006:
http://www.sleeter.com/kbase/kbarticles/1154283981
Dealing with slow data files issues with Quickbooks? While this article is dated for 2006 the infomation pertains to later versions as well.
Try saving as a portable data file and opening that.
Read the complete post at http://msmvps.com/blogs/bradley/archive/2008/02/11/dealing-with-slow-data-files-issues-with-quickbooks.aspx