Hi, i installed nitro pdf v5.4.0.21 and restarted as recomended, but the vista sidebar did not load on startup. i tried all the ways that some of them are listed in this forum and some of them are on the other forums. Result is the same: Vista sidebar could not be loaded! i have read an article about this issue, but it did not solve the problem. here is the link: Windows Vista Sidebar does not load on startup. they suggested to install the latest version, but i have the latest version, already! here is the article: " ..... Q10157 - PRB: Windows Vista Sidebar does not load on startup. The information in this article applies to: * Nitro PDF Professional v5.3.3.6 and below on Vista operating system. Symptoms After installation the Vista Sidebar has been disabled. Cause The problem is due to some DLL files that have not been registered correctly during the installation process. Resolution The DLL files has been updated with v5.4 and later of Nitro. Download and install the latest version from here - Product updates for Nitro PDF Professional (If the above link does not work, please use the alternative link at the bottom of the page) ....." When i click on the Windows Vista Sidebar in accessories, the application starts and stops in half a second. i open up the task manager for all users and track the changes from there. sidebar.exe application strarts and stops immediately. Hence, it's not possible to act on this application. In this article, they say "The problem is due to some DLL files that have not been registered correctly during the installation process."I don't understand this. I cannot see any relation between vista sidebar and the nitropdf's dll files. i think it's impossible. Finally, i hate nitropdf! their answer to this problem is awful! i want to get get my sidebar back i need your help that who installed the nitropdf on vista 32bit home prem. and have the non-corrupted dll files (i still don't know that which files are corrupted) thanks for reading ..