Vlookup function in userform

Hi guys,

Just a newbie here in the forum. I stumbled upon this site in search for an answer from Excel (VBA) experts around the globe. Hope I get to find them here!

My problem is the ever recurring error 1004 ("Unable to get the VLookup property of the worksheetfunction class") whenever I trigger the ComboBox1 in Userform1, Activities tab (I used multipage here).

Here's the code:

HTML Code: 

Also attached is the "sanitized" sample workbook for reference (pardon me if you see my programming skill and structure a bit messy, still newbie here ).

In addition, why does this file keep on popping with message "This workbook contains links to one or more external sources that could be unsafe."? How can I get rid of it?
Hope you can help me with this. This functionality is very crucial in this workbook.
Thanks in advance guys!!!

sample workbook.xlsm

Why do you set the value of the combobox to be equal to ProdID whenever it is changed? Are you actually setting the value of ProdID anywhere? Perhaps you meant

ProdID=ComboBox1.Value

It would also help if you added some data in the Projects sheet so we can check it's working!

Hi,

You are not loading the values while initializing the form in the combo box drop.
Hence the error.
Use error handler - but in this case the resultant output may be the input for the next one.
However see the below updated code for the same but revise once before applying.

Private Sub ComboBox1_Change()
ComboBox1.Value = ProdID
If ProdID = "" Then
    Exit Sub
Else
ProdIDLK = Application.WorksheetFunction.VLookup(ProdID, Sheets("Projects").Range("A5:F30"), 3, False)
TextBox15.Text = ProdIDLK
End If
End Sub

On the point 2 - "This workbook contains links to one or more external sources that could be unsafe."?
There exists a external link in the workbook - break the link and save - it will work fine.

regards,
lokicl

Wow! You guys really rock! Let me absorb first your comments and will get back to you with the result.

Thanks for the prompt responses!

Hi again experts, and thanks from your responses!

I applied your workarounds and still cant get the preferred results. Ok here's the idea: if you look at the Userform1, on the Activities multipage tab, the Project ID combo box gets the RowSource from Projects sheet. Same behavior with Project Name combo box next to it. Upon triggering either combo boxes, the vlookup function should take effect, and values have to be reflecting in Start Date and End Date textbox (which are disabled to prevent manual manipulation) and even in themselves (Project ID and Project Name combo boxes). All these inputs actually came from the Projects tab (in userform) and Projects sheet.

I am attaching again the file with sample inputs in Projects sheet for you guys to have a firm grip on the idea on how this macro should behave.
application behavior.jpg

I am also attaching the screen shot of how the application should behave on change event of either combo boxes.
sample workbook.xlsm

Again million thanks!

Try this

ProdID = val(ComboBox1.Value)

and I would incorporate Andy's point.

Thanks guys for all your inputs. I tried all your suggestions, however they do not return the preferred result. Due to time constraints, I ended up restructuring the user interface of the form and now out of this showstopper. I am no longer be needing this functionality, however for the sake of other forum visitors who are encountering the same predicament, I am not going to tag this as "solved", so that more solutions will surface here.

Thanks a lot guys, and I believe I will be a frequent visitor of this forum from hereon.