I have been in contact with Orange Support but they have been unable to suggest a cause for this sudden change in functionality.

To attempt to diagnose the cause I have: Carried out a full Anti-Virus scan both with my system and online with nothing found. Carried out a full Anti-Malware scan with two separate programs with nothing found. Carried out a HiJackThis scan and submitted the results for analysis with nothing found. Closed all Add-ons in Firefox to ensure there is no conflict. This had no effect. Reinstalled Firefox in case the software was broken. This had no effect. I have tried repeatedly to gain access using IE. Sometimes I can access webmail but it takes several attempts. However, if I get into webmail via IE and then change to Firefox using the button in the lower toolbar I am into webmail in Firefox. This indicates to me that either something in Firefox is blocking the dropdown or there is something incompatible in the Orange web page.

I can access all other areas of Orange and my account that I have always been able to. It appears to be webmail that is affected. I have installed no software between being able to access webmail with Firefox and the problem becoming apparent; i.e. between normal access in the morning and the inability in the evening of the same day.

Does anyone have any other suggestions?

Using Firefox, at the Orange webmail page.

Above the two box outs in the main screen and below the black options bar an orange coloured "check your email" box with registration details fails to drop down as it should.

In IE the "check your email" dropdown appears but only links me to my webmail after a number of attempts sometimes.

In my browser in the bottom toolbar I have a small Firefox logo button which switches between Firefox and IE using IE Tab Plus 2.0.0.0.

Yes, but no changes to any of them between the process working and failing to work. I have also tried with all Add-ons disabled and it still fails to function - even after a full PC restart.

The problem makes no sense to me. If I had installed, uninstalled, updated or modified a process I could understand it more; but for it suddenly not function for no apparent reason ...

I contacted Orange in case they had upgraded something, but as with you they knew of no reason but suggested I update Java and Flash Player in case I was on older versions; my versions are fully up to date as I recognise the security inputs made in updates.