SharePoint 2010 - InfoPath services forcing users to have local client app installed

Dear all

Our college SharePoint environment was recently forced into installing a CU to make it compatible with their workflow.

Upon installing this all users were no longer able to add/edit or make any change to theirs or any other InfoPath form via Internet Explorer.

We have therefore had to install InfoPath form filler across on everyone's machine the campus until I can identify what caused it.

I have not got much background on the particular CU in question having only been in the college 3 days.

Could anyone give me some basic guidance on where to start?

The farm environment is 14.0.7128.5000 SharePoint 2010

Thanks for reading.