This is a very common problem people face while migrating from Blogger to WordPress. You receive 404 error if any mobile user is visiting to your website after searching something on google search engine.
Why ?m=1 parameter is used by Blogger ?
?m=1 parameter is used if a visitor is using any mobile device and based on the parameter blogger optimizes template for small devices like mobile and tablets.
How to Fix ?m=1 Querystring issue ?
Whenever a visitor visits your WordPress based blog with ?m=1 parameter it results in 404 error. This can be handled either by use of a redirection plugin by John Godley or by stripping out ?m1=1 parameter from query string.
If you are having large number of pages, it would be a bit difficult to add redirection one by one. In such cases you can strip ?m=1 by adding below line of code in your .htaccess file.
RewriteEngine On
RewriteCond %{QUERY_STRING} ^m=1$
RewriteRule ^(.*)$ /$1? [R=301,L]
