There are certain usernames that cannot be pm'ed. The reason being is that some characters are getting ignored by html. For example... I was trying to write to user "hotknikklesTM" since the TM is smaller or something around this username is bugging the database therefore it cannot be privately messaged.
Reasons::
mysql or whatever database you're using could do things like " myname" and it looks like "myname". <-- notice that there is a space in the first myname. but html ignores it so when you hit Send PM you get an error that particular user does not exist but they just wrote you?...
at the beginning of the username, you have to physically look in the db. Erwin thats your job man!
hope you can nail it.
Reasons::
mysql or whatever database you're using could do things like " myname" and it looks like "myname". <-- notice that there is a space in the first myname. but html ignores it so when you hit Send PM you get an error that particular user does not exist but they just wrote you?...
at the beginning of the username, you have to physically look in the db. Erwin thats your job man!
hope you can nail it. 
