Thank you, the shown message above indicates a possible cause for your issue - the filesystem used to store the data on your computer somehow got corrupted and is no longer writeable (read-only). This can happen for two possible reasons:
- Your computer unexpectedly shut down during a critical write operation, or
- A hardware fault
Let’s first assume that (1) was the case, so please follow the instructions in the following thread:
The steps outline the procedure on how to boot your computer into a special mode where recovery attempts can be made. Please follow them closely and report back if they worked out.