I am a new wordpress user but I tried this and it worked perfectly (after a lot of frustration).
The .htaccess file is an invisible file – so first you have to find some kind of FTP program that will show you invisible files.
IF you have newly installed WordPress, there will probably be no .htaccess file (especially if, like me, you are installing it for the first time). The .htaccess file should be located in the root of the domain name (eg. https://www.yourdomainhere.com) or in the appropriate blog sub-directory (eg. https://www.yourdomainhere.com/blog).
Take the custom settings given by WordPress under the Permalinks section which are the same for everyone:
# BEGIN WordPress
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteRule . /index.php [L]
# END WordPress
and enter these lines of code into your (hopefully not still invisible) .htaccess file – and save and upload if necessary.
HERE’s WHERE I FOUND THE PROBLEM – – when you edit the file, chances are your text editor (or whatever you used) added some kind of .txt suffix to it. In other words, you may be seeing a normally invisible file named “.htaccess” but, in reality, you have probably just saved a file called “.htaccess.txt” which wordpress can’t recognize. The fact is you just can’t see the “.txt” suffix and you have to remove it before wordpress can write to the file.
The only way I solved this was to SSH shell access into the root of my server and go through a lengthy command process to change it. I needed the help of my tech support to do it – and you might too. Basically just ask them to please check to see if the .htaccess file (located either in your root directory or otherwise as described above) has the .txt suffix attached to it or not. Have them rename it for you (because remember, you can’t necessarily see the suffix even though you can see the invisible file itself).
I’m not a windows user – but apparently, if you can save the file with quotations marks ( ” ” ) around it (eg. “.htaccess”) it will not add an invisible .txt suffix – but don’t quote me on that – I have not tested it.
Also make sure you chmods and mod_rewrite files are working first.
Hope this helps.