Image caption The Price Finder website has been hit by technical difficulties for more than a week

People starting to send Christmas cards and presents from the UK are being hit by problems on a Royal Mail website.

The Price Finder page - which calculates postal costs of packages based on size and weight - has been closed due to "technical difficulties".

Online stamp buying, redirection and redelivery services were also affected on occasions since last Monday.

The Christmas deadline for second-class post is 17 December and is three days later for first-class deliveries.

The problems, lasting more than a week, were caused by a migration of online services to a new computer server.

They come as one consumer watchdog urged people to plan ahead and beat the festive rush.

Glitch

The Price Finder website gives accurate postal cost information, for both UK and overseas mail, based on selections made on drop-down menus.

This includes weight, the location of the recipient, and the level of service required. It is part of a move to encourage people to deal with postal services at home, rather than by queuing at a post office, which includes postage labels and payment on the internet.

Small businesses and those using internet auction sites also use the service when it is operating.

However, anyone visiting the Price Finder site has found a service message explaining that it is not available.

"We are sorry for any inconvenience this is causing. We are working hard to fix these problems as quickly as possible," the message reads.

Image caption Christmas is the busiest time of year for Royal Mail

A Royal Mail spokesman said that the shutdown had been caused by a shift of online services to a new server - a process that had been ongoing for 18 months.

Services that had been affected, with varying degrees, since Monday 21 November included paying for postage online, the smart stamp process allowing small businesses to print postage directly onto envelopes, as well as online redirection and redelivery services.

He apologised and said he hoped everything would be running as normal "very soon". Services were still available as normal in post offices and on the telephone. He said the migration problems had not been anticipated before Christmas.

A document explaining stamp prices is available to download on the Price Finder website, as a temporary replacement to the interactive service.

But businessman Edward Rodden from Swindon, who has been using the mail service for ten years, was unimpressed

"Running a small business, [and being] totally reliant on online postage and smartstamp, I was unable to use it [the site] for a full four days," he said.

Mr Rodden also said that he did not feel his complaints were being taken seriously, and that Royal Mail should face more competition.

'Be prepared'

The problems come as findings by watchdog Consumer Focus - which suffered technical problems with its own website for less than 30 minutes on Thursday - suggested that people lacked planning and awareness of the Christmas rush.

Its survey, of 1,006 UK adults, found that a third of those asked said they would send all their Christmas post by first-class mail.

Stamp prices First-class: 46p

Second-class: 36p

Other prices depend on size and weight Royal Mail price guide

Around eight in 10 did not know the last posting dates for Christmas, including the final day for standard packages of 14 December, and the deadlines for sending overseas of between 5 December and 12 December.

Nearly one in five planned to leave their online and mail order shopping until the week leading up to Christmas.

An estimated 750 million cards will be posted in the UK this Christmas. Second-class stamps cost 36p and have a better delivery record of arriving within three days, than first-class cards - which cost 46p - arriving the next day.

"We would urge people to start thinking about Christmas post and stocking up on second-class stamps now," said Robert Hammond, of Consumer Focus.

"Posting and ordering gifts early will save money and ensure things arrive in plenty of time. Mailing early also gives your postie a fighting chance to deliver the huge surge in Christmas post on time.

"A lot of people seem to be planning to leave things to the last minute and they may be in for a nasty shock if the weather turns for the worst as it did last year."

Letter losses

Royal Mail recently reported pre-tax profits for the six months to 25 September of £187m, up from £50m in the same period last year.

However, this included an operating loss of £41m from the letters and parcels division.

In June 2009, the BBC News website revealed that personal data, including the signatures of recipients had been exposed to those tracking deliveries on the Parcelforce website.

The delivery service, part of the Royal Mail Group, apologised for the failure in the system which allowed people using the mail tracing service access to the name, postcode and signature at various addresses.