1) This error may occur when running a self-extracting Zip file (also known as 'self-extracting archive', or 'SEA') and the filename (or the path it is in) contains one or more Unicode characters. Rename or move the SEA so the path and filename do not contain any Unicode characters, e.g. C:\backup.exe
Beware especially of Unicode characters that mimic standard ASCII characters, such as Unicode versions of quotation marks, apostrophes, etcetera. If in doubt, try deleting and re-typing using standard characters.
2) The same error may be triggered when trying to open (execute) an SEA created by 32-bit versions of SyncBackLite/SE/Pro where the size of the SEA exceeds 2GB (this figure may be subject to slight variation, depending on free memory and other Windows issues). It is in fact a limitation of the maximum size of a 32-bit executable ( SyncBackSE/Pro is available in both 32- and 64-bit versions). Such errors may also trigger a Windows error message about the file 'not being a valid Win32 application', especially if over 4GB.
Possible workarounds are as follows:a) run a Restore with SyncBackSE/Pro on the existing 2GB+ SEA (it will open/extract from the SEA, not try to run it)
b) open the SEA with a 3rd-party Zip utility (provided it can cope with SEAs of that size - most modern utilities can, but you would need to test this yourself). Effectively, same as option-a but with a 3rd-party utility and manual extraction.
c) split the backup into two or more SEAs each of less than 2GB (use two or more profiles, with de/selection and/or filtering, size or age separation, etcetera)
d) switch to using standard Zip archives (stop using SEAs). There is no issue with a Zip over 2GB, just an 'executable'.