Trish,

I would be very surprised if this calculation 'error' was caused by a virus,
the answer is almost certainly simpler and could be that your workbook is
being changed to manual calculation. Try:-

Tools|Option|calculation and select auto.

Because of the way Excel works this change can seem to be happening
randomely but in practice if you open a workbook with calculation set as
manual then any second or subsequent workbook opened will also be set to
manual.

Have a look he-

http://www.decisionmodels.com/calcsecretse.htm

With regard to macro security then never run a macro from an untrusted source.

Mike

"Trish" wrote:

Hello, All!

I have been using a Macro enabled Excel file (.xlsm) for the calculation of
expenses quite a long time.

Once got a $20 short (difference) in the calculation. Even after checking
again and again did not find the reason for the error.

The next day after entering more expenses in the same file got tallied
automatically. Even the earlier days $20 short cleared this time.

Is it because of some macro viruses? The above happened twice in a month. My
AntiVirus Avast free, Adaware etc. declared no virus.

How to safely use a macro enabled excel file?

Thanks for any replies.

Trish

With best regards, Trish. E-mail: