What are a few important tips to remember while importing contacts from excel files?

Tips to remember while importing the excel files:

Column headers should not exceed 255 characters.
File size should not exceed 30 MB.
Avoid using hyperlinks in email addresses.
Add email addresses under the appropriate column headers only.
When saving an Excel file, the format should be saved as MS Excel 95 or later.
When importing an Excel file, make sure to keep contacts on one sheet.
Unexpected errors may occur if an XLS file contains any special controls, combo filters, or images embedded within it.
Checkbox field value should be true or false.
Date values must be in mm/dd/yyyy format. Dates in any other format will be ignored.
DateTime values must be in mm/dd/yyyy hh:mm:ss format. Date Time values in any other format will be ignored.
By default, character encoding is UTF-8 (Unicode). Make sure you provide the correct character encoding if your import file requires a different character code.
We recommend that you test your import with a sample file before you import the actual data.
Though we support Excel files, there is a possibility that it may not work due to other unknown errors. If this happens, we suggest converting your Excel file to a .csv file and trying the import again.