Not clear whether this is what you are looking for€¦

Place the cursor in C1 cell and select
FormatConditional FormattingCondition 1Formula Is
=$C10
Then Click the Format command button and choose your desired Font and
Pattern colour and give Ok Twice.

Now place the cursor in C2 cell and select
FormatConditional FormattingCondition 1Formula Is
=$C1<=0
Then Click the Format command button and choose your desired Font and
Pattern colour and give Ok Twice.

Assume that you would like to apply the conditional formatting Upto C500
cells. Then place the cursor in C1 cell and extend the selection upto C2 cell
by pressing Shift+Down arrow and press Cntrl+C to copy the selection (C1:C2).

Now place the cursor in C3 cell and extend the selection upto C500 and do
right click and select Paste Special (Note: Paste special will be active once
the copy has done, otherwise you cant able to select the Paste Special
Option) and select the Formats Option Button and press Ok. Now the
Conditional formatting is applied upto C500 cells.

The C2 cell formula will highlight the C2 cell when C1 is <=0.
=$C1<=0
The above C2 cell formula will highlight the C2 cell when there is no data
in C2.

So, If you want to set colour for C2 when C1 is <=0 and C2 is not blank,
then use the below formula while applying the conditional formatting for C2
cell.
=AND($C1<=0,$C2<"")

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Remember to Click Yes, if this post helps!

--------------------
(Ms-Exl-Learner)
--------------------


"RobFJ" wrote:

I want to be able to change the background of a cell colour if a second
condition is met - but for the background to remain unchanged if the first
condition is met.

So in the formula below, the background would be yellow if the 'c2'
condition is satisfied.

=if(c10,c1,c2)

My actual formulae are much more complex but if someone can point me in the
right direction in terms of principles that would be great