I have a user with read permission for library with excel files. When user clicks on document it opens in readonly mode, but user has option to edit file and if he does that all changes are saved on server. I think it's strange - read permission should not allow to modify document, but it dose. Any idea how to solve this issue?
[EDIT] So lets sum up: 1) excel file is document library with unique permissions, only I and enother user can access it, all other groups and users excluded; 2) excel file inherits permissions from document library; 3) that user has read permission and all over the site he never gains write permissions directly or trough group; 4) When i with write rights open the file i get pop-up window it asks me I want to read file or edit it, if user opens it - he gets message that this file can be harmfull; 5) Excel file is opened Excel 2010 and states that file is opened in readonly mode from server, but you can click edit workbook and save - saves are made on server; 6) I checked that user can modify any excel file in directory.