Lock range based on cell value

Hi,
I am trying to come up with process for an online Excel sheet which will lock access to a range if a cell is set to "Yes"

Please see below
Capture.JPG


I will be sharing this file so need the locking of the cells to happen automatically.
The conditional cells in column D, Yes/No are already on restricted access to prevent users from selecting.

Really stuck on this so would really appreciate any help here.

Thanks,

you would need to use code to dynamically lock / unlock, however could you use Data Validation rule on your C range relative to value in D?

e.g. highlight C4:C6 and apply a Custom Data Validation rule of:

Formula:

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if C4 is non-numeric, or D4 is Yes, the entry attempt would fail...

Thanks, but I can't seem to get this to work
when I apply the data validation rule and change column D to Yes, I can still edit column C

I have attached a working example.

Thank you so much! I have no idea why that wouldn't work for me but your's works perfectly.
Cheers