help !!vthe conection to paypal stoped working

hello
I was useing opencart for my website
for about a year suddenly with out changing any thing the conection to paypal stopped working the site refer to paypal but this is the massage I get

Internal Server Error
The server encountered an internal error or misconfiguration and was unable to complete your request.

Please contact the server administrator, webmaster@paypal.com and inform them of the time the error occurred, and anything you might have done that may have caused the error.

More information about this error may be available in the server error log.

i contact paypal but they didnt mange to help me with it
do you have any idea about this problem

thank you
Yuval

same problem here today! glad to know it is not just me. where is the problem Paypal or Open cart?