Lock certain cells only if condition exists in another cell

[finjim]

I need to know how to write a macro or function for the following problem in Excel 2010. In Columns A & B, Rows 1 thru 19, there are entries and/or formulas. Row 20 is a sum of of rows 1 thru 19.

Is it possible through a function or macro to protect or lock columns A & B and rows 1 thru 19, if the total in row 20 is above 149.? The previous data in Rows 1 thru 19 would remain and not change or be replaced with other data.

If this is possible, how would I write the command for this. Thank you.

[p24leclerc]

this simple macro copied into your sheet (not in a module) should do it:

Please Login or Register  to view this content.

[finjim]

Thank you for your macro command to solve the problem. You state "this simple macro copied into your sheet (not in a module) should do it:". I don't understand the difference in copying the macro into a sheet rather than a module. Can you tell me how to do this? Thank you.

[p24leclerc]

When you're in VBA editor, you doubleclick on your sheet name then you copy the lines of code in the white page at the right.
This is a special macro called " event procedure" because it is trigger by a specific action done on this sheet only. In this case, any change in the sheet will trigger the macro which looks at specific cells values and do actions.
Hope this help. If not, i can attach a file for you to test.