It is little bit silly ,but as a SharePoint guy one should know about the administration part of the SharePoint which is a heart .If you want to know the last deployment date and time of a solution on web application,just follow the below mentioned steps: 1.go to your central administration 2.click on system security and click on manage farm solution. There you can see your deployed solution and click on the solution.You will come to know the last date and time of the deployment of the solution. Cheers Pradeepa