Macros Diabled - no antivirus, encrypted macros

I have a relatively simple .xls file that I'm trying to convert to a .xlsm file for use in Excel 2010. In compatibility mode I get the option to open the file with macros enabled but once converted it won't allow me to enable macros. I get the following message:

"Security Alert This file contains encrypted macros that have been disabled because there is no antivirus software installed that can scan them. To run these macros, remove the encryption or permission restrictions on the file."

I have tried setting the VBA project properties to NOT locked for viewing, presuming this is what encryption means, but it still won't give me the option to enable. I cannot alter the application security settings as that is controlled centrally. I have converted several other files to .xlsm and they have all been fine, but this one... argh! Is my only option to continue to run it in compatibility mode?

Any ideas appreciated.

TC

What if you convert .xls to .xlsx first and then copy-paste code to this .xlsx and save it as .xlsm?

No Joy - same problem. Was hopeful for a minute there!

Also tried annotating out all code and removing the Command Button embedded in the work sheet.

Can you upload your .xls without any data?

Unfortunately not - at work and uploads are prohibited. I could past the code but not sure that will provide much insight.

Eventually found a fix - appeared to be quite random, but added the network locations to the Trusted Locations in Excel sorted it.

http://www.dummies.com/software/micr...-excel-macros/