How can I troubleshoot my Windows command line crashing even on basic commands like ipconfig?

My Windows command line is crashing even on issuing basic commands like ipconfig:

The dumps include two XML files, WER8B9C.tmp.WERInternalMetadata.xml,

<?xml version="1.0" encoding="UTF-16"?>
<WERReportMetadata>
    <OSVersionInformation>
        <WindowsNTVersion>6.1</WindowsNTVersion>
        <Build>7601 Service Pack 1</Build>
        <Product>(0x1): Windows 7 Ultimate</Product>
        <Edition>Ultimate</Edition>
        <BuildString>7601.18247.amd64fre.win7sp1_gdr.130828-1532</BuildString>
        <Revision>1130</Revision>
        <Flavor>Multiprocessor Free</Flavor>
        <Architecture>X64</Architecture>
        <LCID>1033</LCID>
    </OSVersionInformation>
    <ParentProcessInformation>
        <ParentProcessId>8900</ParentProcessId>
        <ParentProcessPath>C:\Windows\System32\cmd.exe</ParentProcessPath>
        <ParentProcessCmdLine>&quot;C:\Windows\system32\cmd.exe&quot; </ParentProcessCmdLine>
    </ParentProcessInformation>
    <ProblemSignatures>
        <EventType>APPCRASH</EventType>
        <Parameter0>ipconfig.exe</Parameter0>
        <Parameter1>6.1.7600.16385</Parameter1>
        <Parameter2>4a5bcd06</Parameter2>
        <Parameter3>ntdll.dll</Parameter3>
        <Parameter4>6.1.7601.18247</Parameter4>
        <Parameter5>521eaf24</Parameter5>
        <Parameter6>c00000fd</Parameter6>
        <Parameter7>0000000000027c83</Parameter7>
    </ProblemSignatures>
    <DynamicSignatures>
        <Parameter1>6.1.7601.2.1.0.256.1</Parameter1>
        <Parameter2>1033</Parameter2>
        <Parameter22>5b64</Parameter22>
        <Parameter23>5b64b222441f0dcfc8fc8d2866d215f4</Parameter23>
        <Parameter24>4ee8</Parameter24>
        <Parameter25>4ee8565ed192aa79b842845cbdff4288</Parameter25>
    </DynamicSignatures>
    <SystemInformation>
        <MID>7166BCF7-DB8E-49F0-B24F-0357479C638D</MID>
        <SystemManufacturer>LENOVO</SystemManufacturer>
        <SystemProductName>2359CTO</SystemProductName>
        <BIOSVersion>G4ET94WW (2.54 )</BIOSVersion>
    </SystemInformation>
</WERReportMetadata>

and WERD75C.tmp.appcompat.txt,

<?xml version="1.0" encoding="UTF-16"?>
<DATABASE>
<EXE NAME="SYSTEM INFO" FILTER="CMI_FILTER_SYSTEM">
    <MATCHING_FILE NAME="kernel32.dll" SIZE="1161216" CHECKSUM="0xED2A37B2" BIN_FILE_VERSION="6.1.7601.18229" BIN_PRODUCT_VERSION="6.1.7601.18229" PRODUCT_VERSION="6.1.7601.18015" FILE_DESCRIPTION="Windows NT BASE API Client DLL" COMPANY_NAME="Microsoft Corporation" PRODUCT_NAME="Microsoft® Windows® Operating System" FILE_VERSION="6.1.7601.18015 (win7sp1_gdr.121129-1432)" ORIGINAL_FILENAME="kernel32" INTERNAL_NAME="kernel32" LEGAL_COPYRIGHT="© Microsoft Corporation. All rights reserved." VERDATEHI="0x0" VERDATELO="0x0" VERFILEOS="0x40004" VERFILETYPE="0x2" MODULE_TYPE="WIN32" PE_CHECKSUM="0x11EB53" LINKER_VERSION="0x60001" UPTO_BIN_FILE_VERSION="6.1.7601.18229" UPTO_BIN_PRODUCT_VERSION="6.1.7601.18229" LINK_DATE="08/02/2013 02:16:22" UPTO_LINK_DATE="08/02/2013 02:16:22" EXPORT_NAME="KERNEL32.dll" VER_LANGUAGE="English (United States) [0x409]" EXE_WRAPPER="0x0" FILE_ID="00007244ae695f8e5a730857781635acb2969f15c594" PROGRAM_ID="0000f519feec486de87ed73cb92d3cac802400000000" />
    <MATCHING_FILE NAME="ntdll.dll" SIZE="1732032" CHECKSUM="0x7EC8079C" BIN_FILE_VERSION="6.1.7601.18247" BIN_PRODUCT_VERSION="6.1.7601.18247" PRODUCT_VERSION="6.1.7600.16385" FILE_DESCRIPTION="NT Layer DLL" COMPANY_NAME="Microsoft Corporation" PRODUCT_NAME="Microsoft® Windows® Operating System" FILE_VERSION="6.1.7600.16385 (win7_rtm.090713-1255)" ORIGINAL_FILENAME="ntdll.dll.mui" INTERNAL_NAME="ntdll.dll" LEGAL_COPYRIGHT="© Microsoft Corporation. All rights reserved." VERDATEHI="0x0" VERDATELO="0x0" VERFILEOS="0x40004" VERFILETYPE="0x2" MODULE_TYPE="WIN32" PE_CHECKSUM="0x1A875F" LINKER_VERSION="0x60001" UPTO_BIN_FILE_VERSION="6.1.7601.18247" UPTO_BIN_PRODUCT_VERSION="6.1.7601.18247" LINK_DATE="08/29/2013 02:17:08" UPTO_LINK_DATE="08/29/2013 02:17:08" EXPORT_NAME="ntdll.dll" VER_LANGUAGE="English (United States) [0x409]" EXE_WRAPPER="0x0" FILE_ID="00002b1dc5de7a39b95a6c4c2da4645ca47597b16ab5" PROGRAM_ID="0000f519feec486de87ed73cb92d3cac802400000000" />
</EXE>
</DATABASE>
<EXE NAME="ntdll.dll" FILTER="CMI_FILTER_THISFILEONLY">
    <MATCHING_FILE NAME="ntdll.dll" SIZE="1732032" CHECKSUM="0x7EC8079C" BIN_FILE_VERSION="6.1.7601.18247" BIN_PRODUCT_VERSION="6.1.7601.18247" PRODUCT_VERSION="6.1.7600.16385" FILE_DESCRIPTION="NT Layer DLL" COMPANY_NAME="Microsoft Corporation" PRODUCT_NAME="Microsoft® Windows® Operating System" FILE_VERSION="6.1.7600.16385 (win7_rtm.090713-1255)" ORIGINAL_FILENAME="ntdll.dll.mui" INTERNAL_NAME="ntdll.dll" LEGAL_COPYRIGHT="© Microsoft Corporation. All rights reserved." VERDATEHI="0x0" VERDATELO="0x0" VERFILEOS="0x40004" VERFILETYPE="0x2" MODULE_TYPE="WIN32" PE_CHECKSUM="0x1A875F" LINKER_VERSION="0x60001" UPTO_BIN_FILE_VERSION="6.1.7601.18247" UPTO_BIN_PRODUCT_VERSION="6.1.7601.18247" LINK_DATE="08/29/2013 02:17:08" UPTO_LINK_DATE="08/29/2013 02:17:08" EXPORT_NAME="ntdll.dll" VER_LANGUAGE="English (United States) [0x409]" EXE_WRAPPER="0x0" FILE_ID="00002b1dc5de7a39b95a6c4c2da4645ca47597b16ab5" PROGRAM_ID="0000f519feec486de87ed73cb92d3cac802400000000" />
</EXE>
</DATABASE>

as well as a binary file (presumably a memory dump).

I can't figure out what's wrong. This problem prevents me, for example, from installing certain Cygwin packages that run a .sh script as part of the installation, as I get the same crash. Can anyone suggest steps I might take toward diagnosing and fixing this issue?

^{* I don't know if it's related, but the problem started when I was learning Ruby on Rails following steps in Hartl's Ruby on Rails Tutorial. Specifically, I didn't have a problem with installing and using IronRuby, but the problems began when I attempted to install ANSICON 1.60 to get colored output on my command-line. I recall setting some environment variables, not being able to get it to work, undoing those environment variable changes, and having this issue ever since. I've downloaded the latest ANSICON 1.66 and run ansicon.exe -u and ansicon.exe -i to uninstall and reinstall the software, in case it might help, but no luck.}

As per @Braiam's suggestion, I tried sfc /scannow, but with the same results:

Solution 1:

You can verify if ANSICON is really the problem by running cmd /d which starts the command prompt without processing its autorun entry, thus bypassing ANSICON.

If ipconfig now succeeds, then the cause of the problem is indeed ANSICON. If it does not succeed, then try again while booting in Safe mode. Running sfc /scannow in Safe mode is also advised.

If you decide to uninstall ANSICON, use the same cmd /d invocation to do <path>\ansicon -u, or from Safe mode boot if necessary. Use regedit to search for the string "ANSICON" in the registry and delete (very carefully) all entries. Delete all ANSICON files.

If ANSICON is not the problem, then Windows is in a bad shape. Try in this case first to rollback the system to a system restore point dating from before these troubles. If this does not succeed, do a Repair Install, which will fix your Windows installation but preserve user accounts, data, programs, and system drivers.