Nokia Symbian mobile phone firmware data
File type: Mobile phones related file
Files with the mcusw file extension contain firmware for some Nokia mobile phones running Symbian.
They are used as firmware data during phone flashing over a USB cable.
File type category:
Mobile phones related file
Date updated: October 7, 2026
The mcusw file extension is associated with firmware for Nokia mobile phones that use the Symbian operating system. The file contains the phone's MCU software, which is one of the firmware components installed during a flash operation.
These files are used by Nokia flashing tools and can be supplied to tools such as JAF (Just Another Flasher) box software. They are intended for servicing or updating compatible phones rather than for opening as documents or media files.
Open or use an mcusw file with compatible Nokia Flash Tools on Microsoft Windows. The file is normally selected as part of a firmware flashing process for a supported Nokia phone, rather than opened for viewing.
JAF (Just Another Flasher) software and compatible hardware may also use this file during flashing.
An mcusw file is a firmware component, not a document or media file, so it cannot be meaningfully converted to another format.
Use the file only with compatible Nokia flashing software and firmware packages. Converting or editing it may make it unusable for phone flashing.
Software applications that can open mcusw files:
Microsoft Windows
Language
