After installing Office 2013, tasks and main tool boxes disappear in MicroStation V8i SS2, due to Office 2013 install either deletes or unregisters the capicom.dll file located in C:\Windows\System32 folder.
1. Option
Copy the capicom.dll file over and register it, MicroStation v8i SS2 goes back to working as expected.
2. Option
Running a repair of MicroStation also regenerates the capicom.dll file.
3. Option
Other possibility: from Windows 8 Start-> Command Prompt (admin) paste command line (msiexec /i {7E9B0F70-EEF6-41E1-BF89-FDC4B9EDBD9C} REINSTALL=ALL REINSTALLMODE=omus /qb )
and press enter, this will use the SS2 product code to find the MSI that is cached on the machine and repair the MicroStation installation.
see screen shot
http://communities.bentley.com/products/administration/f/343321/t/92320
http://communities.bentley.com/products/microstation/w/microstation__wiki/15905.toolboxes-disappear