The filenames in the Zip file I created using SyncBack are corrupted when opened with Windows or another Zip program

SyncBack stores filenames in Unicode format in Zip files. This allows it to store filenames in many different languages in the same Zip file. Many Zip utilities, including the Zip functionality in Windows File Explorer, are not Unicode aware. Because of this when you view the Zip file using those 3rd party utilities they may show corrupted or invalid filenames for non-English filenames. However, if you use SyncBack itself to restore or view the files then the correct filename will be used.

SyncBack can also be configured to store the filenames in UTF8 format (see Compression->Advanced in the profiles configuration) which may help make the Zip file compatible with some compression utilities.