RM 5.3 doesnt startup anymore

Hey there,
yesterday I was still working with it (latest RM 5.3 with all updates), 32bit version under Windows 8.1 x64, i7-4770k, 16gb Ram, and today I simply couldn't start RM anymore.
No matter how often I clicked on the icon on my desktop, it didn't start.
I searched the forums and it seems that this happened in earlier RM 5.x versions before already but there was no real solution mentioned.
I uninstalled RM 5.3, deleted the whole rapid-i folder in C:\program files (x86)\rapid-i, then reinstalled it freshly and restarted the computer.
But still... it doesn't start anymore.
What could I possibly do?

Java version is:

C:\Users\myuser>java -version java version "1.7.0_55" Java(TM) SE Runtime Environment (build 1.7.0_55-b14) Java HotSpot(TM) Client VM (build 24.55-b03, mixed mode, sharing)

And here some more information about windows:

C:\Users\myuser>ver Microsoft Windows [Version 6.3.9600] C:\Users\myuser>systeminfo Hostname:                                      BLAAAPC Betriebssystemname:                            Microsoft Windows 8.1 Pro N Betriebssystemversion:                         6.3.9600 Nicht zutreffend Build 9 600 Betriebssystemhersteller:                      Microsoft Corporation Betriebssystemkonfiguration:                   Eigenständige Arbeitsstation Betriebssystem-Buildtyp:                       Multiprocessor Free Registrierter Benutzer:                        myuser Registrierte Organisation: Produkt-ID:                                    xyxy-10012-xyxy-xyxy Ursprüngliches Installationsdatum:             18.11.2013, 14:14:49 Systemstartzeit:                               27.05.2014, 10:10:26 Systemhersteller:                              To Be Filled By O.E.M. Systemmodell:                                  To Be Filled By O.E.M. Systemtyp:                                     x64-based PC Prozessor(en):                                 1 Prozessor(en) installiert.                                               [01]: Intel64 Family 6 Model 60 S tepping 3 GenuineIntel ~3500 MHz BIOS-Version:                                  American Megatrends Inc. P1.70, 0 4.07.2013 Windows-Verzeichnis:                           C:\Windows System-Verzeichnis:                            C:\Windows\system32 Startgerät:                                    \Device\HarddiskVolume1 Systemgebietsschema:                           de;Deutsch (Deutschland) Eingabegebietsschema:                          de;Deutsch (Deutschland) Zeitzone:                                      (UTC+01:00) Amsterdam, Berlin, Be rn, Rom, Stockholm, Wien Gesamter physischer Speicher:                  16.314 MB Verfügbarer physischer Speicher:               13.425 MB Virtueller Arbeitsspeicher: Maximale Größe:    19.002 MB Virtueller Arbeitsspeicher: Verfügbar:         15.236 MB Virtueller Arbeitsspeicher: Zurzeit verwendet: 3.766 MB Auslagerungsdateipfad(e):                      C:\pagefile.sys Domäne:                                        WORKGROUP Anmeldeserver:                                 \\MicrosoftAccount Hotfix(es):                                    67 Hotfix(e) installiert.

Please help me ASAP.
Thanks a lot!

Edit: Tried to start as administrator. Doesnt work either. The strange thing is that the same happens to a friend of mine. Yesterday he had to click like 3 times on the icon on his desktop until it did finally start. And also today he doesnt get it running. He is also running 32bit version under Win8.1 x64. For us both, there's not even a process "rapidminer.exe" in the process manager... Very strange!

EDIT2: Wow, I just look into the eventlog of windows, nothing in there. Okay. Then I just really double clicked RM on my desktop again and it started. This sounds very weird and somehow strange to me. Anybody any clue?