This as been asked in 2012 under the title "Outlook 2010 Calendar seems to be empty until switch week forward and back"but I never found the question and answer on this site !!!

I have also this this problem.   As soon I quit the calendar and return, the current week only have therepeated task displayed and not the others.  I need to click on BACK or FORWARD in order to have MY REAL TASK FOR THE WEEKdispalyed. 

(there is also a problem with this site... each time I click on an other window and return, the new characters are in BOLD... continously even if I switch off the BOLD button)