webmail - unable to delete emails - help please

[#1]

I keep getting bombarded by emails from Plusnet telling me that I need to delete emails but every time I log into Plusnet webmail and select the emails I'd like to delete or move to 'deleted messages' the following messages come up

Server Error:Failed to send UID EXPUNGE command or

UID COPY: Courier-IMAP server shut down by signal or

Failed to send FETCH command

Server Error! (error)

Plus the pages on webmail take longer to load that watching paint dry, all I get is a spinning wheel and the message "loading". I'll be old before I can get this thing to work.

Help please, I have over 2000 emails that I need to delete. I'm not particularly computer literate and I never want to be.

[#2]

Moderators Note
This topic has been moved from ADSL Broadband to Email.

[#3]

I'm continually nudging the limit on my IMAP account and the only way I have found to delete emails from Webmail is to do it early in the morning, when there is less traffic on the Plusnet server. (As is the case this morning - look at the time of ths post!)