Stop user from moving to next text box in access form

[Ajit Singh]

Hi
I have a form in which user will enter few values but I need users to enter the comment in relevant text box too only if they have any non zero value.

I have attached an example for reference....where red encircled portion is for values and blue is for relevant comments. If value is non zero then user should be enforced to enter the comment too......system should not allow user to move forward or backward until there is some comment.

Please help with this asap.

 

[spikepl]

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