The problem may be caused by an old version of the certificate of the java applet in the cache of your computer and can be solved by deleting this old certificate.

You can do this as follows:

Microsoft™ Windows PC / Sun™ Java:

In the Control Panel you can find the configuration of the java applet.
The lay-out (interface) may vary per PC.
Here you can delete saved certicates by emptying the java cache.

During the next upload you will automatically be requested to accept a new certificate.

The problem will be solved.

Apple™ Macintosh OSX:

The configuration for Java is almost the same as on a PC.

The configuration programmes can be found in the following folder:

<start up disk>: Programmes: Utilities: java

In most cases you will find plugin settings for java 1.3.x, for java 1.4.x or the most recent for OSX 10.4.x which is: J2SE 5.0
The 1.4 applet is only used by Safari. Mozilla still uses 1.3.

By double clicking on the plug-in settings you will get an overview of the certificates and cache. Here you will be able to delete the saved certificates and to empty the java cache

During the next upload you will automatically be requested to accept a new certificate.

The problem will be solved.

Apple™ Macintosh OS9:

Accepted certificates can be found at the following location:

<start up disk>: System folder: Preferences: identitydb.obj

The problem can be solved by deleting this file.

The cache of the java runtime can be found in the following folder:

<start up disk>: System folder: programme support: MRJ Cache:

Completely emptying this folder will solve the problem.

During the next upload you will automatically be requested to accept a new certificate.

The problem will be solved.