cant open device, where is the problem

i received this error message, what should i do? before 2 days my arduino worked perfect, i already reinstalled the arduino software. please help me

ארדואינו:1.6.8 (Windows 8.1), לוח:"Arduino/Genuino Uno" Sketch uses 3,990 bytes (12%) of program storage space. Maximum is 32,256 bytes. משתנים גלובלים משתמשים ב-216 בייט (10%) של זיכרון דינמי, משאיר 1,832 בייט לאחסון משתנים מקומיים. מרב המקום הוא 2,048 בייטים. avrdude: ser_open(): can't open device "\.\COM6": ‏‏הגישה נדחתה. בעיה בטעינה ללוח בקר ב: לקבלת עצות. This report would have more information with "Show verbose output during compilation" option enabled in File -> Preferences.

Another program is open, and connected to the serial port, or it could be an unusual manifestation of driver problems (usually driver problems = no com port at all, but a couple of people on these forums have reported a COM port that gave access denied until they installed drivers).

Make sure you don't have any other programs open that might be using the port (serial monitors/consoles/terminals using the port, typically), and make sure you have the right port selected.

For others, the part of the error that matters says "Access Denied"

i found the problem. a wire was connected to 0; thx