You have attempted a database restore in Analysis Services from a .abf file and get the error : “The file specified in the restore command is damaged or is not an AS backup file. The following system error occurred : Access is denied”. The key clue in the error is the last part.
Go to the actual file, i.e. not the folder, right click, select properties, the click the Security tab. Edit the file’s security so that the Analysis Services service account has sufficient permissions i.e. full permissions will work. If you don’t know the Analysis Services Services account, go to SQL Server Configuration Manager and find your Analysis Services service where you will see the service account.