I found the issue! If you're using Default-Checker-Gray, the build will fail on iOS.

Not fixed in 2019.2. Come on, guys. This is ludicrous.

Hi everyone.
We are facing the same issue building for IOs:

DXT1 compressed textures are not supported when publishing to iPhone
Resources/unity_builtin_extra
Included from scene:
UnityEngine.GUIUtility:ProcessEvent(Int32, IntPtr)

There is any way to delete all references to Resources/unity_builtin_extra?
i have checked all across the hierarchy and removed all uses, but build still failed.
also tried to delete the components in the canvas and the canvas itself, the build succeeded in this case. so the problem is still in the canvas

Still an issue at 2019.3.x - but thank you @UNITY_CBPSC0SA9JZR1W that fixed it for me.

Hi guys! I am having this issue and I am new to unity too, I don't know where to find this "native textures" can help with this please?

For those ppl who have this issue and using ES2/ES3 (Easy Save) plugin. Just delete easy save manager from hierarchy, not from asset. This manager will appears again imediatly, but issue will be solved.

My solution was the same as @unity_CbPSc0Sa9jzr1w using a native texture as a texture.

Hi.
I also had the same problem
"DXT1 compressed textures are not supported when publishing to iPhone
Resources/unity_builtin_extra
Included from scene: ".

After researching about an hour I figured out the error reason.
The error says that "Resources/unity_builtin_extra" is included from Scene.
In my project on some 3D object I used native texture.
So I stopped using that native texture and the build went well.

I hope this will help others as well.

Still happens in 2018.4.9f1

hi,
plaise help me same error but in unity 2019.3.0a5

Debug log :

DXT1 compressed textures are not supported when publishing to iPhone
Resources/unity_builtin_extra
Included from scene:
0 Unity 0x000000010f08213f _Z13GetStacktracei + 95
1 Unity 0x0000000111849a54 _Z17DebugStringToFileRK21DebugStringToFileData + 356
2 Unity 0x000000010e61d572 _Z23VerifyFeatureDeploymentP6Object19BuildTargetPlatform + 2082
3 Unity 0x000000010e613209 _Z16VerifyDeploymentP6Object19BuildTargetPlatform + 1273
4 Unity 0x000000010ef2fdcc _ZN17PersistentManager9WriteFileERKN4core12basic_stringIcNS0_20StringStorageDefaultIcEEEEiPK9WriteDataiRK15GlobalBuildDataPF23VerifyWriteObjectResultP6Object19BuildTargetPlatformE20BuildTargetSelection24TransferInstructionFlagsR16WriteInformationPK18InstanceIDResolverNS_9LockFlagsE + 3084
5 Unity 0x000000010ef2f093 _ZN17PersistentManager9WriteFileERKN4core12basic_stringIcNS0_20StringStorageDefaultIcEEEEiPK9WriteDataiRK15GlobalBuildDataPF23VerifyWriteObjectResultP6Object19BuildTargetPlatformE20BuildTargetSelection24TransferInstructionFlagsPK18InstanceIDResolverNS_9LockFlagsE + 179
6 Unity 0x000000010e61235b _Z20WriteSharedAssetFileiRKN4core12basic_stringIcNS_20StringStorageDefaultIcEEEERKNSt3__13mapIi10BuildAssetNS6_4lessIiEENS6_9allocatorINS6_4pairIKiS8_EEEEEERK19BuildUsageTagGlobal20BuildTargetSelectionPFviR31LocalSerializedObjectIdentifierPvE24TransferInstructionFlagsRNS6_3setI12ResourceFileNS9_ISU_EENSB_ISU_EEEER10vector_mapIi26SerializedObjectIdentifierSA_NSB_INSC_IiS10_EEEEE + 1099
7 Unity 0x000000010e613597 _Z23CompileSharedAssetsFileiRKN4core12basic_stringIcNS_20StringStorageDefaultIcEEEES5_RKNSt3__13mapIi10BuildAssetNS6_4lessIiEENS6_9allocatorINS6_4pairIKiS8_EEEEEERK19BuildUsageTagGlobalRK20BuildTargetSelection24TransferInstructionFlagsRNS6_3setI12ResourceFileNS9_ISR_EENSB_ISR_EEEER10vector_mapIi26SerializedObjectIdentifierSA_NSB_INSC_IiSX_EEEEERN14BuildReporting11BuildReportE + 135
8 Unity 0x000000010e62b966 _ZL15BuildPlayerData24BuildTargetPlatformGroup19BuildTargetPlatform18BuildPlayerOptionsRK16BuildCompressionNSt3__16vectorIN4core12basic_stringIcNS7_20StringStorageDefaultIcEEEENS5_9allocatorISB_EEEEP20AssetBundleBuildDataRNS6_I17EditorSceneBackup13stl_allocatorISH_L18MemLabelIdentifier116ELi16EEEE18ScriptingObjectPtr8Vector2fRN14BuildReporting11BuildReportERKSB_PNSP_20BuiltAssetBundleInfoEST_ + 12038
9 Unity 0x000000010e600753 _Z13DoBuildPlayerRK16BuildPlayerSetupRNSt3__16vectorI17EditorSceneBackup13stl_allocatorIS4_L18MemLabelIdentifier116ELi16EEEEN4core12basic_stringIcNSA_20StringStorageDefaultIcEEEENS3_ISE_NS2_9allocatorISE_EEEEbRN14BuildReporting11BuildReportEPNSI_20BuiltAssetBundleInfoERKSE_ + 3587
10 Unity 0x000000010e605196 _Z11BuildPlayerRK16BuildPlayerSetupRN14BuildReporting11BuildReportE + 4102
11 Unity 0x000000010f74fa94 _Z47BuildPipeline_CUSTOM_BuildPlayerInternalNoCheckP36ScriptingBackendNativeArrayPtrOpaqueP37ScriptingBackendNativeStringPtrOpaqueS2_24BuildTargetPlatformGroup19BuildTargetPlatform18BuildPlayerOptionsh + 1204
12 (Mono JIT Code) (wrapper managed-to-native) UnityEditor.BuildPipeline:BuildPlayerInternalNoCheck (string[],string,string,UnityEditor.BuildTargetGroup,UnityEditor.BuildTarget,UnityEditor.BuildOptions,bool)
13 (Mono JIT Code) [BuildPlayerWindowBuildMethods.cs:170] UnityEditor.BuildPlayerWindow/DefaultBuildMethods:BuildPlayer (UnityEditor.BuildPlayerOptions)
14 (Mono JIT Code) [BuildPlayerWindowBuildMethods.cs:96] UnityEditor.BuildPlayerWindow:CallBuildMethods (bool,UnityEditor.BuildOptions)
15 (Mono JIT Code) [BuildPlayerWindow.cs:913] UnityEditor.BuildPlayerWindow:GUIBuildButtons (UnityEditor.Modules.IBuildWindowExtension,bool,bool,bool,UnityEditor.Build.BuildPlatform)