When you open a file as UTF-8 (no bom) (byte order mark) format, make some changes and press 'Save as' to save it with another name, Toad tries to save the file as ANSI encoding and every time it needs to be manually changed back UTF-8 (no bom). Default setting is set to this UTF-8 (no bom) with Unix (LF) (Line feed).
There is no difference between UTF-8 encoding and ANSI if the source text is simple ASCII characters from 0-127. When you save the file as UTF-8 (no BOM) and then the file is reloaded, Toad sees that there is no BOM and thus tries to identify multibyte UTF-8 characters. If there are none, then the file is both ANSI and UTF-8 (no BOM). Both the scenarios are correct.
WORKAROUND:
Select the type of encoding manually every time a pre-saved file is saved again.
STATUS:
Enhancement request TOR-8891 has been submitted to Development for consideration in a future release of Toad for Oracle
