I have had numerous issues with Itunes 64 bit 11.1.38 (and other previous versions) locking up and crashing upon start with "Itunes has stopped working" or "R6027 pure virtual function call". I have researched the answers around the forums as well as having tried some extensive and repetitious troubleshooting myself and thought I'd list them here... in order of troubleshooting...
1. Install all Windows updates and reboot. This seems to clear issues from time-to-time... I suspect Itunes expects the latest-and-greatest as far as Windows is concerned.. see if this clears your issue.
2. Uninstall all Itunes and Apple products & reboot, remove their directories, remove lingering Itunes registry entries, reboot again, reinstall using "RUN AS ADMINISTRATOR" to install the Itunes executable. See if this allows Itunes to stabilize. Pelase be sure to use the following guide from Apple as far as removing the apps and directories are concerned...
http://support.apple.com/kb/ht1923
3. Remove the contents of the "iphone photo cache" (or other related product photo cache) directory.
4. Try editing the shortcut properties and configure the shortcut (for all users) to run as Administrator.
5. Try editing the shortcut and configure it to run in Compatibility Mode for Windows 7 (for all users).
6. a.Try using MSCONFIG to locate a potential conflicting application or service using the following...
http://support.apple.com/kb/ht2292
or
6. b. Remove the last recent software application(s) you may have installed... in my case removing GREENSHOT http://getgreenshot.org/ stopped my Itunes from crashing on startup and it stabilized after
driving my nuts for weeks.
Message was edited by: DaCheeze