Programs dissapearing

Tech Support Guy System Info Utility version 1.0.0.2
OS Version: Microsoft Windows 8.1, 64 bit
Processor: Intel(R) Core(TM) i5-2320 CPU @ 3.00GHz, Intel64 Family 6 Model 42 Stepping 7
Processor Count: 4
RAM: 8096 Mb
Graphics Card: Intel(R) HD Graphics, -1988 Mb
Hard Drives: C: Total - 481675 MB, Free - 420949 MB; E: Total - 458777 MB, Free - 189661 MB; K: Total - 1430795 MB, Free - 916319 MB; L: Total - 2861578 MB, Free - 1765857 MB; M: Total - 61035 MB, Free - 60997 MB; O: Total - 476937 MB, Free - 51069 MB;
Motherboard: Gateway, IPISB-VR
Antivirus: Windows Defender, Disabled, Norton 360

I installed Office 365 about a month ago and used it several times. Today I went to use Word and it is not there. It is not in the programs list in the uninstall programs. Then I started looking for the other programs in the suite and the only one that is there although not in the uninstall programs is excell which I attached to the task bar, but I can use the spreadsheets.

3 days ago I installed Lightroom 5 and it also has dissapeared. My husband has had the same problems with office.

I would appreciate any help on this.