Usually this error occurs when the maximum allowed connection limit of the database has exceeded. It also means that the database already has enough number of open connections and cannot allow anymore. In that case you can either wait for someone to disconnect or if incase a specific script has opened too many connections to the database all at once.In such a scenario, you must follow these simple steps :
Step 1- Login into windows server using RDP.
Step 2- Edit the file:
C:\Program Files\Paralles\Plesk\MySQL\Data\my.ini
In this file search for the maximum set limit under settings max_user_connections. You may either choose to increase the value OR remove the max_user_connections parameter.
NOTE: Removal of the max connections parameter would apply the default MySQL settings to the database.
That’s all to do, i hope it will help to resolve the issue.
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