c# - visual studio 2013 crash on opening xsl -

every time open .xsl file visual studio 2013 update 4 crashes. error message below. pretty useless. suggestions?

i running vs in administrator security context (run as). can open , debug on local iis 7.5 (instead of vs debugger / port).

i did install azure , ssdt extensions (vwdorvs2013azurepack.exe , ssdtsetup.exe). latter failed install correctly.

error below. thanks!

application: devenv.exe framework version: v4.0.30319 description: process terminated due unhandled exception. exception info: system.security.securityexception stack: @ system.security.codeaccesssecurityengine.check(system.object, system.threading.stackcrawlmark byref, boolean) @ system.security.codeaccesssecurityengine.check(system.security.codeaccesspermission, system.threading.stackcrawlmark byref) @ system.security.codeaccesspermission.demand() @ system.reflection.runtimeassembly.verifycodebasediscovery(system.string) @ system.reflection.runtimeassembly.getname(boolean) @ system.reflection.assembly.getname() @ microsoft.visualstudio.design.toolbox.autotoolboxmanagerservice.onassemblyloadworker(system.reflection.assembly) @ microsoft.visualstudio.design.toolbox.autotoolboxmanagerservice+<>c__displayclass2.b__0() @ system.windows.threading.exceptionwrapper.internalrealcall(system.delegate, system.object, int32) @ ms.internal.threading.exceptionfilterhelper.trycatchwhen(system.object, system.delegate, system.object, int32, system.delegate) @ system.windows.threading.dispatcheroperation.invokeimpl() @ system.windows.threading.dispatcheroperation.invokeinsecuritycontext(system.object) @ system.threading.executioncontext.runinternal(system.threading.executioncontext, system.threading.contextcallback, system.object, boolean) @ system.threading.executioncontext.run(system.threading.executioncontext, system.threading.contextcallback, system.object, boolean) @ system.threading.executioncontext.run(system.threading.executioncontext, system.threading.contextcallback, system.object) @ system.windows.threading.dispatcheroperation.invoke() @ system.windows.threading.dispatcher.processqueue() @ system.windows.threading.dispatcher.wndprochook(intptr, int32, intptr, intptr, boolean byref) @ ms.win32.hwndwrapper.wndproc(intptr, int32, intptr, intptr, boolean byref) @ ms.win32.hwndsubclass.dispatchercallbackoperation(system.object) @ system.windows.threading.exceptionwrapper.internalrealcall(system.delegate, system.object, int32) @ ms.internal.threading.exceptionfilterhelper.trycatchwhen(system.object, system.delegate, system.object, int32, system.delegate) @ system.windows.threading.dispatcher.legacyinvokeimpl(system.windows.threading.dispatcherpriority, system.timespan, system.delegate, system.object, int32) @ ms.win32.hwndsubclass.subclasswndproc(intptr, int32, intptr, intptr)

faulting application name: devenv.exe, version: 12.0.31101.0, time stamp: 0x54548724 faulting module name: kernelbase.dll, version: 6.1.7601.18839, time stamp: 0x553e88ab exception code: 0xe0434352 fault offset: 0x0000c42d faulting process id: 0x2260 faulting application start time: 0x01d09ec4b4de9874 faulting application path: c:\program files (x86)\microsoft visual studio 12.0\common7\ide\devenv.exe faulting module path: c:\windows\syswow64\kernelbase.dll report id: dc09e38b-0ab8-11e5-9e99-10bf48466a8d 

i worked around issue. renamed xsl extension xml. worked on file. rename xsl before testing. did several weeks, maybe month.

one day accidentally opened xsl file before renaming it. thought, "oh no! going crash", didn't , haven't experienced problem since.

if had guess, i'd vs cached bad. overtime, editing cleared cache , pink fluffy unicorns dancing on rainbows again.