https://community.graphisoft.com/t5/Modeling/Building-Material-Name-Auto-Number-Extension/m-p/188367#M102083 That is a feature that started with AC17 so you might need to read the Migration Document for the full reason.<BR /> <BR /> Basically when importing (or copy paste) from an older version file into AC17 or 18 some materials will be duplicated when they are applied to a different surface. For example you have 2 Surfaces, one red and one blue that have the same 25% fill assigned to them then Building mats will create 2 different Building Materials and append the number. For same Building Mats then you can use the "Delete and Replace" option Sun, 13 Jul 2014 13:08:47 GMT Eduardo Rolon 2014-07-13T13:08:47Z https://community.graphisoft.com/t5/Modeling/Building-Material-Name-Auto-Number-Extension/m-p/188366#M102082 <DIV class="actalk-migrated-content"><T>Hi,<BR /> <BR /> As seen in the attached file, some Building Material Names are duplicated with auto-number extension.<BR /> <BR /> What is the reason?</T></DIV><BR /><IMG src="http://community.graphisoft.com/t5/image/serverpage/image-id/71975i7F97B0E494368CA4/image-size/large?v=v2&amp;px=999" border="0" alt="2014-07-12 Building Material Window - Yellow Areas.PNG" title="2014-07-12 Building Material Window - Yellow Areas.PNG" /> Sun, 13 Jul 2014 12:42:29 GMT https://community.graphisoft.com/t5/Modeling/Building-Material-Name-Auto-Number-Extension/m-p/188366#M102082 adura 2014-07-13T12:42:29Z https://community.graphisoft.com/t5/Modeling/Building-Material-Name-Auto-Number-Extension/m-p/188367#M102083 That is a feature that started with AC17 so you might need to read the Migration Document for the full reason.<BR /> <BR /> Basically when importing (or copy paste) from an older version file into AC17 or 18 some materials will be duplicated when they are applied to a different surface. For example you have 2 Surfaces, one red and one blue that have the same 25% fill assigned to them then Building mats will create 2 different Building Materials and append the number. For same Building Mats then you can use the "Delete and Replace" option Sun, 13 Jul 2014 13:08:47 GMT https://community.graphisoft.com/t5/Modeling/Building-Material-Name-Auto-Number-Extension/m-p/188367#M102083 Eduardo Rolon 2014-07-13T13:08:47Z https://community.graphisoft.com/t5/Modeling/Building-Material-Name-Auto-Number-Extension/m-p/188368#M102084 Thank you <I></I><S><I><I></I></I></S>ejrolon<E></E>, Then I'll clean the old attributes.<BR /> <BR /> Best regards... Sun, 13 Jul 2014 14:12:32 GMT https://community.graphisoft.com/t5/Modeling/Building-Material-Name-Auto-Number-Extension/m-p/188368#M102084 adura 2014-07-13T14:12:32Z