403.0 modsecurity action on windows server

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Windows

security

errors

Hello,

I have a database application. Has been running for years. Its a PHP/MySQL application.

Over the past several months various clients get a 403.0 ModSecurity Action when they log in. The strange thing is, that when I try their user name and password, I log in just fine, no error. And I have tried it on several computers and various other networks. Its only a handful of clients that get this error. 98% of the clients that use the database application are fine.

My question, why would only a few get this error? What would I check to figure out how to resolve this?

Thanks in advance for any help.

What I have tried:

I have tried these logins on 10 different computer, on 10 different networks. of the 10 only 1 system got the error. I used the same user name and password on all tests.