How do I do a new clean installation

[ladydolphin]

Hi there

Anyone help please.  Just started using, had a problem with the way I 
imported a couple of QIF files and after having a play with software 
decided best thing was to uninstall, delete everything and start with 
clean installation.  Unfortunately despite uninstalling in a number of 
ways, deleting everything I can find that might be connected with 
Gnucash and trying to reinstall a number of times all the new 
installations are showing records of these previous files. Consequently 
an error message is coming up each time with 'The file/URI 
E:\****.gnucash could not be found.  This information is hiding 
somewhere and I don't know where to find it.

Please how do I completely remove everything connected with my trial run 
so that I am able to start again?

Many thanks

Linda