Programmatically generated zip invalid on pc but not on android -
solved: ok stupid. couldn't open file because forgot install winrar or 7zip since pc newly formatted... works fine. sorry waste anyone's time. in app programmatically generate .zip file photos , .csv files in directory. it creates zip , sends email attachment without hickup. problem on pc can't extract .zip file because says it's invalid, on device using "winzip" can check .zip file , has suppose have. confusing me. here code: here check checkboxes have been checked zipping for(int = 0; < cbstates.size(); ++i) { if(cbstates.get(i)) { string zipfile = environment.getexternalstoragedirectory() + "/arcflash/" + listitems.get(i) + ".zip";//ex: /storage/sdcard0/arcflash/study12.zip string srcdir = environment.getexternalstoragedirectory() + "/arcflash/" + listitems.get(i); try { ...