Then go to Applications > Utilities folder and open Disk Utility. In Disk Utility, select your hard disk in left column (the first one in the list will be your hard disk), then Repair Permission. After that click Verify Disk and if asked to repair, click Repair Disk.
Please let me know if that didn't work, so we can continue troubleshooting.
Which is the option key?
Thanks I will try what you suggested shortly. I am concerned that it's a software issue and that it shouldn't be chargeable as it's not something I've done. What is the view on this?
Oh I thought it was apple - that's what I put into the search engine. It looks like it's part of Apple. Maybe you need to make that clear at the outset as I believe apple would have helped me with no charge otherwise. I will try your fix - I assume it won't put my data at risk?
ok. here goes
I have rebooted . Went to apps and can't find a utilities folder - where is it please?
Sorry Ashik - am I meant to find this in Applications? can't see it - expect it's staring me in the face but I can't find it
I typed applications folder into the spotlight box in apps but it doesn't come up with anything by that name and they are in alphabetical order
Ashik, thank you for your patience. I have done what you said and followed your advice but I am still faced with the slow multi coloured beach ball for too long when I try to open applications. When I try and type emails there is a few seconds delay before the text appears. Any other suggestions?
Thanks Ashik, that worries me as I can't risk losing any data. The reason I updated to Yosemite was because my iPhone wouldn't connect with the old software and that's where the problems started. I appreciate your help but it hasn't solved the issue in a safe way for me. I will have to take my computer into Apple after all.
Can I leave you a tip without it being added to the £29 or is it instead of the charge? It's not clear