Sorry, I do not understand what you were asking and tried to guess what was your problem in my reply.
You are writing that you were able to open in browser the forms that "
have been designed to open in the filler application"
AFAIK, Infopath Filler Form cannot be opened in browser while Web Browser Form can be opened both in browser and in Infopath Filler
The publishing wizard of Web Browser Form presents an option:
- Enable this form to be filled out by using a browse
which is absent in publishing wizard of Infopath Filler Form
And if to try opening an Infopath Filler Form in browser, the error is:
- This form template is not currently browser enabled
which is quite logical considering that client forms have richer set of features not supported in browser forms.