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+The most frequent reasons of errors.
+
+### Failed to prepare a workspace
+* Source files or directories use too long names.
+
+### Source directory is empty
+* Selected directory don't contain any image files.
+
+### Failed to extract images from PDF file
+* PDF file have too complex structure.
+* Images inside PDF file are not JPG.
+
+### Failed to extract archive
+* Archive is corrupted.
+* Archive have password.
+* Archive is multipart.
+* Files or directories inside use too long names.
+
+### Failed to detect archive format
+* Archive is corrupted or use unsupported format.
+
+### Image file X is corrupted
+* Specified file is damaged and cannot be processed.
+
+### Target directory is not writable
+* KCC don't have rights to create files in directory containing source files.
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