In 4.7.2 I’ve no light build issues. But if I open the same project with 5.0.3, which will create a copy, light buidling fails and shows those in the message.log:
LogLightmassSolver: Warning: Failed to open channel for material data for D5493D2047EECBF0F469E98A1C9CC2B8: /Game/VictorianExteriors/Materials/Glass/M_Glass_01.M_Glass_01
LogLightmassSolver: Warning: Failed to open channel for material data for 6C695333473D9589F905EF8C4DCCE83A: /Game/VictorianExteriors/Materials/Walls/Plaster/MI_Paint_Plaster_01_01.MI_Paint_Plaster_01_01
LogLightmassSolver: Warning: Failed to open channel for material data for B9FB4CB44932C5845547169B1D429CD1: /Game/VictorianExteriors/Materials/Walls/Bricks/M_Exterior_Bricks_01.M_Exterior_Bricks_01
LogLightmassSolver: Warning: Failed to open channel for material data for A2EAF6AC4095292272C59591C7884861: /Game/VictorianExteriors/Materials/Concrete/M_Concrete.M_Concrete
LogLightmassSolver: Warning: Failed to open channel for material data for 0332794B41B409B7B7AB77BA488A13D4: /Game/VictorianExteriors/Materials/Wood/M_Wood_01.M_Wood_01
LogLightmassSolver: Warning: Failed to open channel for material data for E7D065E14588675F5F5092A8D13B0CEE: /Game/VictorianExteriors/Materials/Walls/Plaster/MI_Paint_Plaster_01_07.MI_Paint_Plaster_01_07
LogLightmassSolver: Warning: Failed to open channel for material data for 6EAB8B224A6F8B15759F19BDF8EACBE3: /Game/VictorianExteriors/Materials/Metals/M_Cast_Iron_Metal.M_Cast_Iron_Metal
LogLightmassSolver: Warning: Failed to open channel for material data for E572A3504467FE3C9105B0A5220D8806: /Game/VictorianExteriors/Materials/Roof/MI_Tiles_01_01.MI_Tiles_01_01
LogLightmassSolver: Warning: Failed to open channel for material data for 48388E1948D3A4AA81EC92AA0D83DAC0: /Game/VictorianExteriors/Materials/Walls/Plaster/MI_Paint_Plaster_01_02.MI_Paint_Plaster_01_02
LogLightmassSolver: Warning: Failed to open channel for material data for 13F968D945BA7180F49A3786A090A3E8: /Game/VictorianExteriors/Materials/Columns/M_Classical_Doric_Column.M_Classical_Doric_Column
LogLightmassSolver: Warning: Failed to open channel for material data for 827F61924C02FFFEE24CB1B8A0C2E79B: /Game/VictorianExteriors/Materials/Walls/Plaster/MI_Paint_Plaster_01_04.MI_Paint_Plaster_01_04
LogLightmassSolver: Warning: Failed to open channel for material data for 078B568246447D0DD91523BB2165F62B: /Game/VictorianExteriors/Materials/Metals/ExteriorLamp/M_Cast_Iron_Metal_Exterior_Lamp_01.M_Cast_Iron_Metal_Exterior_Lamp_01
LogLightmassSolver: Warning: Failed to open channel for material data for 612A2705499601DD6C5ACDAD89179761: /Game/VictorianExteriors/Materials/Metals/ExteriorLamp/MI_Cast_Iron_Metal_02.MI_Cast_Iron_Metal_02
LogLightmassSolver: Warning: Failed to open channel for material data for 76DF1B404F88EE8D35279E8FF7F4C4B7: /Game/VictorianExteriors/Materials/Lamps/Lights/MI_Light_Bulbe_01_01_ON.MI_Light_Bulbe_01_01_ON
LogLightmassSolver: Warning: Failed to open channel for material data for 19E488554E5DCD48724E8B83A5402C2C: /Game/VictorianExteriors/Materials/Glass/M_Dirty_Glass_01.M_Dirty_Glass_01
LogLightmassSolver: Warning: Failed to open channel for material data for 412663634E494B5D881CCBAAD5EAFD0C: /Game/Ivy_Foliage_Pack_4K/Materials/M_IvyFoliage_Wind_Inst.M_IvyFoliage_Wind_Inst
LogLightmassSolver: Warning: Failed to open channel for material data for C43710EC41C58373686C04BB660E98AD: /Game/VictorianExteriors/Materials/Walls/Concrete/MI_Concrete_Bricks_01.MI_Concrete_Bricks_01
LogLightmassSolver: Warning: Failed to open channel for material data for 6B14AE8B4C72B830B3EE98B89B77D32A: /Game/Speakeasy/Materials/MI_Picture_Frames.MI_Picture_Frames
LogLightmassSolver: Warning: Failed to open channel for material data for 9B1A69AE4361B8AE0B26BB91124F8517: /Game/Speakeasy/Materials/MI_ArtWork_1.MI_ArtWork_1
LogLightmassSolver: Warning: Failed to open channel for material data for D35835D947D66EB3D56BAB9E4FA243B0: /Game/Speakeasy/Materials/MI_ArtWork_2.MI_ArtWork_2
LogLightmassSolver: Warning: Failed to open channel for material data for B38D82BF4200C7311B60C2B131713CF1: /Game/Speakeasy/Materials/MI_ArtWork_3.MI_ArtWork_3
LogLightmassSolver: Warning: Failed to open channel for material data for 33D6CD2141D40CFE568A57A2C974C09A: /Game/VictorianExteriors/Materials/Metals/ExteriorLamp/M_Cast_Iron_Metal_Exterior_Lamp_02.M_Cast_Iron_Metal_Exterior_Lamp_02
LogLightmassSolver: Warning: Failed to open channel for material data for A0A3BA6B4E32539D2A0907A50B8474C9: /Game/VictorianExteriors/Materials/Metals/ExteriorLamp/M_Cast_Iron_Metal.M_Cast_Iron_Metal
LogLightmassSolver: Warning: Failed to open channel for material data for 534AC8B2430F1B5E04309582BEE77FD0: /Game/VictorianExteriors/Materials/Metals/MI_Golden_Metal_01.MI_Golden_Metal_01
LogLightmassSolver: Warning: Failed to open channel for material data for 1F04A21E47812886E6CB9CAAC05FC81A: /Game/VictorianExteriors/Materials/Metals/ExteriorLamp/M_Cast_Iron_Metal_Exterior_Wall_Lamp_Base.M_Cast_Iron_Metal_Exterior_Wall_Lamp_Base
LogLightmassSolver: Warning: Failed to open channel for material data for 7761981C4A02A75596244F861814DB7C: /Game/VictorianExteriors/Materials/Walls/Plaster/MI_Paint_Plaster_01_05.MI_Paint_Plaster_01_05
LogLightmassSolver: Warning: Failed to open channel for material data for 61BEAF10406A80A765EF708F731CF6B0: /Game/Biagitown_night.Biagitown_night:PersistentLevel.BP_CarSedan_2.Mesh.MaterialInstanceDynamic_0
LogLightmassSolver: Warning: Failed to open channel for material data for 789B868E4A5D2A87C121D4976FE8C46F: /Game/EuropeanAlleys/Materials/MI_PlasticC.MI_PlasticC
LogLightmassSolver: Warning: Failed to open channel for material data for CFA9832D4F8F60E1DAAF00824F6AA26E: /Game/EuropeanAlleys/Materials/M_Glass.M_Glass
LogLightmassSolver: Warning: Failed to open channel for material data for D7A4C3A1478A1E8D3D84649E9AF1067A: /Game/EuropeanAlleys/Materials/M_Chrome.M_Chrome
LogLightmassSolver: Warning: Failed to open channel for material data for 571892FE484AEC35542ED59E2084D3D3: /Game/EuropeanAlleys/Materials/M_CarDetailsB.M_CarDetailsB
LogLightmassSolver: Warning: Failed to open channel for material data for 6E848A5C457F3BD52B4E6FB82744DB0D: /Game/EuropeanAlleys/Materials/M_Silhouette.M_Silhouette
LogLightmassSolver: Warning: Failed to open channel for material data for 2FFD248E4DD6AF6E333555831BED84FD: /Game/VictorianExteriors/Materials/Nature/M_Bush_Leaves.M_Bush_Leaves
LogLightmassSolver: Warning: Failed to open channel for material data for 684EB5AD4DB520A4BD95DFA51E437016: /Game/VictorianExteriors/Materials/Nature/M_Picea_Abies_Trunk.M_Picea_Abies_Trunk
LogLightmassSolver: Warning: Failed to open channel for material data for FD1AF5824C880F10ED19169B117D74E3: /Game/Street_Decorations/Material/MI_Fence_post_03_Inst.MI_Fence_post_03_Inst
LogLightmassSolver: Warning: Failed to open channel for material data for 6349639542692D1B80095AAE8B078395: /Game/Street_Decorations/Material/MI_Fence_03_Base_Inst.MI_Fence_03_Base_Inst
LogLightmassSolver: Warning: Failed to open channel for material data for C0CCBB9A43EC3C810E60979DBCA92E6A: /Game/Street_Decorations/Material/MI_Fence_03_Leaves_Inst.MI_Fence_03_Leaves_Inst
LogLightmassSolver: Warning: Failed to open channel for material data for C739F0114394681D15AAA4BB4B1A4AF6: /Game/Street_Decorations/Material/MI_Fence_03_LOD_Inst.MI_Fence_03_LOD_Inst
LogLightmassSolver: Warning: Failed to open channel for material data for F52A6788461193567923A78B84F0D611: /Game/Biagitown_night.Biagitown_night:PersistentLevel.Ultra_Dynamic_Sky_6.Ultra_Dynamic_Sky_Sphere.MaterialInstanceDynamic_0
LogLightmassSolver: Warning: Failed to open channel for material data for 680FDB7B4B0C07CDCA959F847F651AED: /Game/Buildings/AbandonedBar/Materials/MM_BlackFill.MM_BlackFill
LogLightmassSolver: Warning: Failed to open channel for material data for 2211EE944B91F68BE80398AB36123935: /Game/VictorianInteriors/Materials/Floors/Ceramic/MI_Marble_Ceramic_Floor_01_05.MI_Marble_Ceramic_Floor_01_05
LogLightmassSolver: Warning: Failed to open channel for material data for 8F9959464AA2D3093C824A96FDF26E3A: /Game/VictorianInteriors/Materials/Floors/Ceramic/M_Marble_Ceramic_Floor_01.M_Marble_Ceramic_Floor_01
LogLightmassSolver: Warning: Failed to open channel for material data for 8E4B0EE04534176922BED5A277A30EBA: /Game/VictorianInteriors/Materials/Walls/Plaster/MI_Paint_Plaster_01_06.MI_Paint_Plaster_01_06
LogLightmassSolver: Warning: Failed to open channel for material data for 09F57B8A419B65A960BD48A326CFF96F: /Game/Office_Vol_1/Materials/Carpets/MI_Carpet_004.MI_Carpet_004
LogLightmassSolver: Warning: Failed to open channel for material data for AF6382554DBBE7154AD81F824497DB4A: /Game/VictorianExteriors/Materials/Concrete/MI_Concrete.MI_Concrete
LogUObjectHash: Compacting FUObjectHashTables data took 1.14ms
LogLightmassSolver: Warning: Error, AddTask failed with error code -13
LogLightmassSolver: Warning: Error, AddTask failed with error code -13
LogLightmassSolver: Warning: Error, AddTask failed with error code -13
LogLightmassSolver: Warning: Error, AddTask failed with error code -13
LogLightmassSolver: Warning: Error, AddTask failed with error code -13
LogLightmassSolver: Warning: Error, AddTask failed with error code -13
LogLightmassSolver: Warning: Error, AddTask failed with error code -13
LogLightmassSolver: Warning: Error, AddTask failed with error code -13
LogLightmassSolver: Warning: Error, AddTask failed with error code -13
LogLightmassSolver: Warning: Error, AddTask failed with error code -13
LogLightmassSolver: Warning: Error, AddTask failed with error code -13
LogLightmassSolver: Warning: Error, AddTask failed with error code -13
LogLightmassSolver: Warning: Error, AddTask failed with error code -13
LogLightmassSolver: Warning: Error, AddTask failed with error code -13
LogLightmassSolver: Warning: Error, AddTask failed with error code -13
LogLightmassSolver: Warning: Error, AddTask failed with error code -13
I’ve recreated this issue by doing the same process again.
What it does as well that some of the same materials from one asset from marketplace I bought are fine with 4.7.2. But with 5.0.3 some of these materials are not shown in the editor instead the worldgridmaterial. Despite the material actually exist.
5.1 I haven’t tried yet due to the missing plugin of substance, but I may try just to see, what happens.
I haven’t come across such an issue with previously going to higher versions.