Inquiry consists of seeking information of knowledgeable persons (both financial and nonfinancial information) throughout the entity or outside the entity. Inquiry is used extensively throughout the audit and often is complementary to performing other audit procedures.
Inquiry may range from formal written inquiries to informal oral inquiries.
30 April 2015
There is a very simple answer here - there is no difference in meaning. The spelling with 'e' is British, the spelling with 'i' is North American. The same goes for the nouns, 'inquiry' and 'enquiry'. There are of course other differences in spelling between American and British English.