Symptoms: Steam won't launch, nothing happens when you click the icon, crash reports show EXC_CRASH (SIGKILL) with Termination Reason: CODESIGNING 1 Taskgated Invalid Signature.
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Translated Report (Full Report Below)
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Incident Identifier: C14EC837-F940-4E2F-BBED-4B55C6D168A3
CrashReporter Key: DEAE9995-A019-4BC0-8D56-C0CD92137EE2
Hardware Model: Mac16,8
Process: steam_osx [27132]
Path: /private/var/folders/*/Steam.app/Contents/MacOS/steam_osx
Identifier: com.valvesoftware.steam
Version: 6.0
Code Type: X86-64 (Translated)
Role: Unspecified
Parent Process: launchd [1]
Coalition: com.valvesoftware.steam [44555]
Date/Time: 2026-04-03 18:18:39.0425 +0200
Launch Time: 2026-04-03 18:18:38.1045 +0200
OS Version: macOS 15.7.3 (24G419)
Release Type: User
Report Version: 104
Exception Type: EXC_CRASH (SIGKILL (Code Signature Invalid))
Exception Codes: 0x0000000000000000, 0x0000000000000000
Termination Reason: CODESIGNING 1 Taskgated Invalid Signature
Triggered by Thread: 0
Thread 0 Crashed:
0 main_executable_path_missing 0x7ff7ffbf219c 0x7ff7ffbef000 + 12700
Thread 0 crashed with X86 Thread State (64-bit):
rax: 0x0000000000000000 rbx: 0x0000000000000000 rcx: 0x0000000000000000 rdx: 0x0000000000000000
rdi: 0x0000000000000000 rsi: 0x0000000000000000 rbp: 0x0000000000000000 rsp: 0x0000000000000000
r8: 0x0000000000000000 r9: 0x0000000000000000 r10: 0x0000000000000000 r11: 0x0000000000000000
r12: 0x0000000000000000 r13: 0x0000000000000000 r14: 0x0000000000000000 r15: 0x0000000000000000
rip: <unavailable> rfl: 0x0000000000000203
tmp0: 0x0000000000000000 tmp1: 0x0000000000000000 tmp2: 0x0000000000000000
Binary Images:
0x200d53000 - 0x200dedfff dyld_path_missing (*) <1a622d74-549f-3f53-bd70-412bd11345e8> /dyld_path_missing
0x7ff7ffbef000 - 0x7ff7ffc1efff main_executable_path_missing (*) <e1f1f05c-bc3d-3c2c-b87c-d85a3f811426> /main_executable_path_missing
0x0 - 0xffffffffffffffff ??? (*) <00000000-0000-0000-0000-000000000000> ???
Error Formulating Crash Report:
dyld_process_snapshot_get_shared_cache failed
RIP register does not match crashing frame (0x0 vs 0x7FF7FFBF219C)
EOF
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Full Report
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{"app_name":"steam_osx","timestamp":"2026-04-03 18:18:39.00 +0200","app_version":"","slice_uuid":"7a7fd838-ffbd-3bee-8ba2-76d23ee141a6","build_version":"6.0","platform":0,"bundleID":"com.valvesoftware.steam","share_with_app_devs":1,"is_first_party":1,"bug_type":"309","os_version":"macOS 15.7.3 (24G419)","roots_installed":0,"name":"steam_osx","incident_id":"C14EC837-F940-4E2F-BBED-4B55C6D168A3"}
{
"uptime" : 81000,
"procRole" : "Unspecified",
"version" : 2,
"userID" : 501,
"deployVersion" : 210,
"modelCode" : "Mac16,8",
"coalitionID" : 44555,
"osVersion" : {
"train" : "macOS 15.7.3",
"build" : "24G419",
"releaseType" : "User"
},
"captureTime" : "2026-04-03 18:18:39.0425 +0200",
"codeSigningMonitor" : 2,
"incident" : "C14EC837-F940-4E2F-BBED-4B55C6D168A3",
"pid" : 27132,
"translated" : true,
"cpuType" : "X86-64",
"roots_installed" : 0,
"bug_type" : "309",
"procLaunch" : "2026-04-03 18:18:38.1045 +0200",
"procStartAbsTime" : 1961687118147,
"procExitAbsTime" : 1961709492201,
"procName" : "steam_osx",
"procPath" : "\/private\/var\/folders\/*\/Steam.app\/Contents\/MacOS\/steam_osx",
"bundleInfo" : {"CFBundleVersion":"6.0","CFBundleIdentifier":"com.valvesoftware.steam"},
"parentProc" : "launchd",
"parentPid" : 1,
"coalitionName" : "com.valvesoftware.steam",
"crashReporterKey" : "DEAE9995-A019-4BC0-8D56-C0CD92137EE2",
"appleIntelligenceStatus" : {"state":"unavailable","reasons":["assetIsNotReady","siriAssetIsNotReady","notOptedIn"]},
"codeSigningID" : "",
"codeSigningTeamID" : "",
"codeSigningFlags" : 16777216,
"codeSigningValidationCategory" : 0,
"codeSigningTrustLevel" : 4294967295,
"codeSigningAuxiliaryInfo" : 0,
"bootSessionUUID" : "4E7654D0-DCAB-4598-91B6-3494E196151A",
"wakeTime" : 91,
"sleepWakeUUID" : "D7FB3EC1-2A38-4588-BFF6-957CBFC3025B",
"sip" : "enabled",
"exception" : {"codes":"0x0000000000000000, 0x0000000000000000","rawCodes":[0,0],"type":"EXC_CRASH","signal":"SIGKILL (Code Signature Invalid)"},
"termination" : {"flags":66,"code":1,"namespace":"CODESIGNING","indicator":"Taskgated Invalid Signature"},
"extMods" : {"caller":{"thread_create":0,"thread_set_state":0,"task_for_pid":0},"system":{"thread_create":0,"thread_set_state":0,"task_for_pid":0},"targeted":{"thread_create":0,"thread_set_state":0,"task_for_pid":0},"warnings":0},
"faultingThread" : 0,
"threads" : [{"triggered":true,"id":4906948,"threadState":{"flavor":"x86_THREAD_STATE","rbp":{"value":0},"r12":{"value":0},"rosetta":{"tmp2":{"value":0},"tmp1":{"value":0},"tmp0":{"value":0}},"rbx":{"value":0},"r8":{"value":0},"r15":{"value":0},"r10":{"value":0},"rdx":{"value":0},"rdi":{"value":0},"r9":{"value":0},"r13":{"value":0},"rflags":{"value":515},"rax":{"value":0},"rsp":{"value":0},"r11":{"value":0},"rcx":{"value":0},"r14":{"value":0},"rsi":{"value":0}},"frames":[{"imageOffset":12700,"imageIndex":1}]}],
"usedImages" : [
{
"source" : "P",
"arch" : "x86_64",
"base" : 8603906048,
"size" : 634880,
"uuid" : "1a622d74-549f-3f53-bd70-412bd11345e8",
"path" : "\/dyld_path_missing",
"name" : "dyld_path_missing"
},
{
"source" : "P",
"arch" : "arm64",
"base" : 140703124353024,
"size" : 196608,
"uuid" : "e1f1f05c-bc3d-3c2c-b87c-d85a3f811426",
"path" : "\/main_executable_path_missing",
"name" : "main_executable_path_missing"
},
{
"size" : 0,
"source" : "A",
"base" : 0,
"uuid" : "00000000-0000-0000-0000-000000000000"
}
],
"vmSummary" : "ReadOnly portion of Libraries: Total=1168K resident=0K(0%) swapped_out_or_unallocated=1168K(100%)\nWritable regions: Total=34.3M written=224K(1%) resident=224K(1%) swapped_out=0K(0%) unallocated=34.0M(99%)\n\n VIRTUAL REGION \nREGION TYPE SIZE COUNT (non-coalesced) \n=========== ======= ======= \nSTACK GUARD 56.0M 1 \nStack 8176K 1 \nVM_ALLOCATE 25.8M 7 \nVM_ALLOCATE (reserved) 148K 2 reserved VM address space (unallocated)\n__DATA 204K 4 \n__DATA_CONST 28K 1 \n__DATA_DIRTY 8K 2 \n__LINKEDIT 368K 3 \n__TEXT 812K 2 \n__TPRO_CONST 4K 1 \nmapped file 9.2G 39 \npage table in kernel 224K 1 \n=========== ======= ======= \nTOTAL 9.3G 64 \nTOTAL, minus reserved VM space 9.3G 64 \n",
"legacyInfo" : {
"threadTriggered" : {
}
},
"logWritingSignature" : "0f53aed76db426edbb34fb3c0251c0dd2cf2bbea",
"trialInfo" : {
"rollouts" : [
{
"rolloutId" : "63508950b3714d3622fc77f7",
"factorPackIds" : {
"SIRI_MEMORY_SYNC_CONFIG" : "6526e111d0c9ce2f459b54a8"
},
"deploymentId" : 240000015
},
{
"rolloutId" : "645197bf528fbf3c3af54105",
"factorPackIds" : {
"SIRI_VALUE_INFERENCE_PERVASIVE_ENTITY_RESOLUTION" : "663e65b4a1526e1ca0e288a1"
},
"deploymentId" : 240000002
}
],
"experiments" : [
]
},
"reportNotes" : [
"dyld_process_snapshot_get_shared_cache failed",
"RIP register does not match crashing frame (0x0 vs 0x7FF7FFBF219C)"
]
}
Model: Mac16,8, BootROM 13822.61.10, proc 12:8:4 processors, 48 GB, SMC
Graphics: Apple M4 Pro, Apple M4 Pro, Built-In
Display: Color LCD, 3024 x 1964 Retina, Main, MirrorOff, Online
Memory Module: LPDDR5, Micron
AirPort: spairport_wireless_card_type_wifi (0x14E4, 0x4388), wl0: Jun 24 2025 04:56:40 version 23.40.31.0.41.51.179 FWID 01-435c4c4d
IO80211_driverkit-1485.12 "IO80211_driverkit-1485.12" Oct 7 2025 20:28:11
AirPort:
Bluetooth: Version (null), 0 services, 0 devices, 0 incoming serial ports
Network Service: Wi-Fi, AirPort, en0
USB Device: USB31Bus
USB Device: USB31Bus
USB Device: USB31Bus
Thunderbolt Bus: MacBook Pro, Apple Inc.
Thunderbolt Bus: MacBook Pro, Apple Inc.
Thunderbolt Bus: MacBook Pro, Apple Inc.
Steam ships as a thin bootstrapper at /Applications/Steam.app. On first launch it downloads the real Steam client and installs it to:
~/Library/Application Support/Steam/Steam.AppBundle/
Every subsequent launch, the bootstrapper just hands off to that Steam.AppBundle. This is how Steam updates itself without needing admin privileges — the actual client lives in your home directory, not in /Applications.
When that AppBundle has a broken or outdated code signature, macOS's taskgated daemon kills the process the moment it tries to run. The bootstrapper in /Applications/Steam.app appears perfectly healthy, which makes this confusing to diagnose.
Running the usual checks:
codesign --verify --deep --strict --verbose=2 /Applications/Steam.app
spctl --assess --type execute --verbose=4 /Applications/Steam.appBoth return clean results — accepted, Notarized Developer ID — because they're checking the bootstrapper, not the binary that actually runs.
Check the UUID in the crash report. Open the .ips file in ~/Library/Logs/DiagnosticReports/ and look for slice_uuid near the top:
{"slice_uuid":"7a7fd838-ffbd-3bee-8ba2-76d23ee141a6", ...}Then check the UUID of the binary in the AppBundle:
otool -arch all -l ~/Library/Application\ Support/Steam/Steam.AppBundle/Steam/Contents/MacOS/steam_osx | grep uuidIf the UUIDs match, this is your culprit. Verify the broken signature directly:
codesign --verify --verbose=4 ~/Library/Application\ Support/Steam/Steam.AppBundle/Steam/A broken install will say something like:
invalid Info.plist (plist or signature have been modified)
Delete the corrupted AppBundle — your games and Steam data are safe, they live elsewhere under ~/Library/Application Support/Steam/:
rm -rf ~/Library/Application\ Support/Steam/Steam.AppBundleThen launch Steam. The bootstrapper will download a fresh, properly signed client automatically.
The AppBundle is managed entirely by Steam's own updater. A few things can leave it in a broken state:
- A Steam update that was interrupted mid-way
- macOS modifying the
Info.plist(e.g. during a system update or migration) - A very old cached
AppBundlefrom a previous install that never got replaced
The tell-tale sign is a binary timestamped years behind the bootstrapper in /Applications/Steam.app.
The UUID mismatch is the crux of this diagnosis. Crash reports always embed the UUID of the binary that actually crashed. If that UUID doesn't match the binary you're inspecting, you're looking in the wrong place. Always cross-reference slice_uuid from the crash report with otool ... | grep uuid on your suspects.
Thank you for sharing this solution. It worked perfectly for me.
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