Shradha_S 270007543G Visits (4810)
If you are using RTC's Pessimistic locking feature, it doesn't work for third party editors like Microsoft Office.
For the above issue, a defect has been identified with third party editors. Below are links to the related defects:
--> Open any Microsoft Office extension (.docx) file using "Open with" option in external editor, the file remains in read-only mode and saving change in the files gives an option to do a "Save As", rather than updating the original file.
To summarize, the read-only doesn't work if the file is edited with Eclipse embedded editor, but the same works if the files is opened using an External editor.
You can also refer the below link for more details: