https://community.graphisoft.com/t5/Archicad-C-API/PLN-and-PLA-file-header-structure-DataRecovery-purpose/m-p/245865#M5429 <DIV class="actalk-migrated-content">Hi. This might seem a little unusual topic on this forums. My client is ArchiCAD user. He recently had a system crash. Files cannot be recovered from that storage, but another drive might have residual data on it. <BR />I tried all methods, but haven't got any good results. <BR /><BR />My last resort is RAW scan. For this I need to define file header. <BR />I took few samples and noticed, that I could use <BR /> <PRE>52 4F 46 20 46 44 42 20 10 00 02 00 00 00 01 01 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 42 4C 04 00 00 00 E8 FD 01 B1 80</PRE> <BR /><BR />This is a good start, although from those few samples I cannot distinguish PLN from PLA files. <BR /><BR />I can't see any pattern at the end of the file, but perhaps the header stores the size of the file itself somewhere? <BR /><BR />That would save my customer's a lot of trouble if I could find some data (even part of it) from that drive. <BR />Some might be quite big, and fragmentation is a big problem here, but it would be at least some chance to get that. <BR /><BR />Any help would be really appreciated. <BR /><BR />Regards, <BR />Paul.</DIV> Tue, 01 Aug 2023 11:39:31 GMT Anonymous 2023-08-01T11:39:31Z https://community.graphisoft.com/t5/Archicad-C-API/PLN-and-PLA-file-header-structure-DataRecovery-purpose/m-p/245865#M5429 <DIV class="actalk-migrated-content">Hi. This might seem a little unusual topic on this forums. My client is ArchiCAD user. He recently had a system crash. Files cannot be recovered from that storage, but another drive might have residual data on it. <BR />I tried all methods, but haven't got any good results. <BR /><BR />My last resort is RAW scan. For this I need to define file header. <BR />I took few samples and noticed, that I could use <BR /> <PRE>52 4F 46 20 46 44 42 20 10 00 02 00 00 00 01 01 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 42 4C 04 00 00 00 E8 FD 01 B1 80</PRE> <BR /><BR />This is a good start, although from those few samples I cannot distinguish PLN from PLA files. <BR /><BR />I can't see any pattern at the end of the file, but perhaps the header stores the size of the file itself somewhere? <BR /><BR />That would save my customer's a lot of trouble if I could find some data (even part of it) from that drive. <BR />Some might be quite big, and fragmentation is a big problem here, but it would be at least some chance to get that. <BR /><BR />Any help would be really appreciated. <BR /><BR />Regards, <BR />Paul.</DIV> Tue, 01 Aug 2023 11:39:31 GMT https://community.graphisoft.com/t5/Archicad-C-API/PLN-and-PLA-file-header-structure-DataRecovery-purpose/m-p/245865#M5429 Anonymous 2023-08-01T11:39:31Z