|On the other hand, I ran both 2003 and 2010 for a while and I had numerous problems.|
Since I use a Personal macro work book, there was often "confusion" as to which application was using which Personal macro workbook. It caused some strange interactions between the 2 versions.
I also had issues with some office apps going through an install process whenever I tried to open them due to registration conflicts.
Bottom line, here's what MS says at the link below:
You can install and use more than one version of Microsoft Office on a single
computer. For example, you can install and use both Microsoft Office 2013 and
Microsoft Office 2010 on the same computer. However, we do not recommend this.
You might want to start here and click on some of the other version links to match your exact situation.
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