[MC-72246] Minecraft is crashing after starting Multi- or Singleplayer

Since about a week I can't play Minecraft anymore.
First, I couldn't start it anymore because I deleted to .minecraft folder to check if it works but then there always were ''Loading versions'' and nothing happend.
I tried to turn off Firewall/Anti-Virus Program but it didnt help.
Then I asked my friend to send me his Minecraft files and now I can start it, but everytime when I try to start a singleplayer world it just crashes.
If I try to connect to multiplayer then it comes 'java.lang.nullPointerExecption :group'' and btw. all Servers are offline.
I already deleted and updated Java installed new Windows Updates etc.
Sorry for my bad english, I'm german.

Related issues

duplicates

MC-34749 Hopper: java.lang.IllegalStateException: failed to create a child event loop - Caused by AntiVirus / Firewall software

Attachments

crash-2014-09-22_08.54.25-client.txt

Comments

migrated 2014-09-22T13:20:44Z

[media]

CubeTheThird 2014-09-22T15:21:50Z

Duplicate of MC-34749. Something like your antivirus or firewall software is blocking java.

This is a technical support issue; this site is for bug reports only. For technical support please use the Mojang Support Center.

migrated 2014-09-23T14:13:31Z

Sorry for doing this on the wrong site, but anyway.
Turning off AntiVirus and Firewall doesnt help, can you help me anyway please?
EDIT: even adding an exeption in the programm doesnt help.

migrated 2014-09-23T14:15:27Z

Respectfully, I believe the gentleman above already answered that question:
"This is a technical support issue; this site is for bug reports only. For technical support please use the Mojang Support Center."