I'm just trying out PyCharm and immediately got nailed with the following error:
"The JVM could not be started. The maximum heap size (-Xmx) might be too large or an antivirus or firewall tool could block the execution."
I found a few random and possibly related references to this error, and eventually stumbled on the file "C:\Program Files (x86)\JetBrains\PyCharm 2.0.2\bin\pycharm.exe.vmoptions". In there I played with -Xmx number, and found that 200 will run.
I don't actually have any idea what this number means, or whether my IDE will keep workingor not, but so far so good. This sounds like something the installer should verify.
I'm running Windows 7 x64 and MacAfee Endpoint Protection if that makes any difference.